Modding:Coding An Item: Difference between revisions

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This guide does not cover adding custom icons.
This guide does not cover adding custom icons.


== Sample Templates ==
Please do remember it is best practise to unpack and consult the game files directly.
*[https://www.nexusmods.com/baldursgate3/mods/3862 Mod Builder] by ReallyLazyIcarus. A python script that generates a folder workspace and empty lsx in the correct format to be converted with the multitool. Recommended!
*[https://www.nexusmods.com/baldursgate3/mods/5165 BG3 Equipment Generator] by Bytebard. A new program, it looks to be a promising new way to add items.
*
Unfortunately a lot of template armour mods are out of date, usually because the mod tools became more efficient. For example most of the [https://bg3.wiki/wiki/Modding:Race_UUID race UUIDS] mentioned on these are defunct and some of the metas don't work. They are still useful to learn from and much of the code will still work, but it is not recommended to use them as a template, just a learning tool.
*[https://www.nexusmods.com/baldursgate3/mods/400 Sample 3D Edited Equipment Mod] by AnteMaxx**A template mod for datamined and 3D edited armor modding. Contains 1 armor, 1 pair of mismatched boots, 1 pair of mismatched gloves, 1 headwear and 1 shoulder armor. Mainly a modder's resource, but can be enjoyed by players as well.
*[https://www.nexusmods.com/baldursgate3/mods/278 Sample Magic Ring Mod] by AnteMaxx
**A template mod for magic ring and spell modding. Contains 4 magic rings. Mainly a modder's resource, but can be enjoyed by players as well.
*[https://www.nexusmods.com/baldursgate3/mods/249 Sample Equipment Mod] by AnteMaxx
**A template mod for Armor and Weapon modding, and for implementing custom icons. Contains 3 armors, 1 weapon and 1 backpack. Mainly a modder's resource, but can be enjoyed by players as well.
*[https://www.nexusmods.com/baldursgate3/mods/1808 BG3 Creator's Cauldron]- an older program. Useful for its long lists of armor.txt and passives for you to use.
*[https://www.nexusmods.com/baldursgate3/mods/502 BG3 MiniTool by Padme4000]- Can generate a [[Modding:Creating meta.lsx|Meta]] for you to use.
==File Overview ==
==File Overview ==



Revision as of 14:16, 30 December 2023

Bgwiii.png CommunityGuidesModding

Modding guides
Modding resources


You have made a mesh for a human man, a circlet. We are going to add it to the game. (See here for how to make new meshes in Blender!)

Remember to check your naming conventions for .lsf.lsx files so the multitool correctly converts them, and keep in mind that some lsx files should not be converted to lsf at all.

Be sure to also check [Modding:Sample_Templates Sample templates.] for further reference.

This guide does not cover adding custom icons.

Sample Templates

Please do remember it is best practise to unpack and consult the game files directly.

  • Mod Builder by ReallyLazyIcarus. A python script that generates a folder workspace and empty lsx in the correct format to be converted with the multitool. Recommended!
  • BG3 Equipment Generator by Bytebard. A new program, it looks to be a promising new way to add items.

Unfortunately a lot of template armour mods are out of date, usually because the mod tools became more efficient. For example most of the race UUIDS mentioned on these are defunct and some of the metas don't work. They are still useful to learn from and much of the code will still work, but it is not recommended to use them as a template, just a learning tool.

  • Sample 3D Edited Equipment Mod by AnteMaxx**A template mod for datamined and 3D edited armor modding. Contains 1 armor, 1 pair of mismatched boots, 1 pair of mismatched gloves, 1 headwear and 1 shoulder armor. Mainly a modder's resource, but can be enjoyed by players as well.
  • Sample Magic Ring Mod by AnteMaxx
    • A template mod for magic ring and spell modding. Contains 4 magic rings. Mainly a modder's resource, but can be enjoyed by players as well.
  • Sample Equipment Mod by AnteMaxx
    • A template mod for Armor and Weapon modding, and for implementing custom icons. Contains 3 armors, 1 weapon and 1 backpack. Mainly a modder's resource, but can be enjoyed by players as well.
  • BG3 Creator's Cauldron- an older program. Useful for its long lists of armor.txt and passives for you to use.
  • BG3 MiniTool by Padme4000- Can generate a Meta for you to use.

File Overview

Your mod is MySweetMod

  • MySweetMod
    • Generated
    • Public
        • MySweetMod
          • Assets <- models and textures
    • Localization
      • Language <- usually English
        • MySweetMod.loca <- text for items and spells
    • Mods
    • Public
      • Game
        • Assets
      • MySweetMod
        • Assets
        • Content
            • Assets
              • Characters
                • [PAK]_Armor <-- material and mesh LSX for custom outfits and weapons
        • GUI
          • RootTemplates <--- Your Roottemplate lsx goes here. MySweetMod.Lsx
          • Stats
              • Generated <--- TreasureTable.txt - This tells the game where the item will spawn.
                • Data <--- Armor.txt, Object.txt, Passive.txt, Weapon.txt and other TXT files. These contain stats.

Meshes.lsx

First we export our mesh, HUM_M_CLT_Headwear_Circlet_Silver_A, from Blender to the MySweetMod/Generated/Public/MySweetMod/Assets Folder.

We now create 2 lsf.lsx for our MySweetMod\Public\MySweetMod\Content\Assets\Characters\[PAK]_Armor.

In these will be a visualbank (list of meshes),a materialbank (list of materials) and a texturebank (list of textures). You can split them into their own pages or combine them all, it doesn't matter. When the multitool converts them they will all get merged together anyway. This separation is for viewer ease as they can become very long. For our needs we are putting them into 2 lsx, a meshes and a texture/material one.

First, the meshes.lsx.

 <version major="4" minor="0" revision="4" build="602" />
 	<region id="VisualBank">
 		<node id="VisualBank">
           <children>
           (START OF ITEM MESH)
 <node id="Resource">
<attribute id="AttachBone" type="FixedString" value="" />
<attribute id="AttachmentSkeletonResource" type="FixedString" value="" />
<attribute id="BlueprintInstanceResourceID" type="FixedString" value="" />
<attribute id="BoundsMax" type="fvec3" value="0.08509202 1.868147 0.04280814" />
<attribute id="BoundsMin" type="fvec3" value="-0.08422767 1.793357 -0.1403362" />
<attribute id="ClothColliderResourceID" type="FixedString" value="" />
<attribute id="HairPresetResourceId" type="FixedString" value="" />
<attribute id="HairType" type="uint8" value="0" />
<attribute id="ID" type="FixedString" value="00000000000000000000000000001" /> (This UUID links up to the Roottemplate)
<attribute id="MaterialType" type="uint8" value="0" />
<attribute id="Name" type="LSString" value="HUM_M_CLT_MySweetCirclet" /> Referenced nowhere else but try to make it unique so you don't potentially mess up another item.
<attribute id="NeedsSkeletonRemap" type="bool" value="False" />
<attribute id="RemapperSlotId" type="FixedString" value="" />
<attribute id="ScalpMaterialId" type="FixedString" value="" />
<attribute id="SkeletonResource" type="FixedString" value="" />
<attribute id="SkeletonSlot" type="FixedString" value="" />
<attribute id="Slot" type="FixedString" value="Headwear" />
<attribute id="SoftbodyResourceID" type="FixedString" value="" />
<attribute id="SourceFile" type="LSString" value="Generated/Public/MySweetMod/Assets/HUM_M_CLT_Headwear_Circlet_Silver_A.GR2" /> (Remember to set your own filepath for your meshes correctly.)
<attribute id="SupportsVertexColorMask" type="bool" value="False" /> You need this set to True if you want, say, pants to vanish when boots are equipped.
<attribute id="Template" type="FixedString" value="Generated/Public/MySweetMod/Assets/HUM_M_CLT_Headwear_Circlet_Silver_A.Dummy_Root.0" /> (Remember to set your own filepath for your meshes correctly. Dummy Root may need to be renamed in Blender as a bone part depending on what you are making)
<attribute id="_OriginalFileVersion_" type="int64" value="144115207403209020" />

<children>
<node id="AnimationWaterfall">
<attribute id="Object" type="FixedString" value="" />
</node>
<node id="Base">
<children>
<node id="Tags">
<attribute id="Object" type="FixedString" value="Never Hide Hair" />
</node>
</children>
</node>
<node id="ClothProxyMapping" />

<node id="Objects">
<attribute id="LOD" type="uint8" value="0" /> What level of LOD it is. This is a LOD0, so it is the highest quality mesh and the one we see in cutscenes.
<attribute id="MaterialID" type="FixedString" value="00000000000000000000004" /> What material it links up to (see materialbank code).
<attribute id="ObjectID" type="FixedString" value="HUM_M_CLT_Headwear_Circlet_Silver_A.HUM_M_CLT_Headwear_Circlet_Silver_A_Mesh.0" /> The .0 denotes mesh order, which is not the same as LOD. It is set in the Blender export. 
</node>


<node id="Objects"> Extra entry for a Level of Detail mesh, which will be seen from a certain distance from the camera. In this case the LOD1.
<attribute id="LOD" type="uint8" value="1" /> This is a LOD1 mesh.
<attribute id="MaterialID" type="FixedString" value="00000000000000000000004" /> 
<attribute id="ObjectID" type="FixedString" value="HUM_M_CLT_Headwear_Circlet_Silver_A.HUM_M_CLT_Headwear_Circlet_Silver_A_Mesh_LOD1.1" /> 
</node>

Note that this is a circlet, so it doesn't need to hide any part of the body. But if it had that code, it would go here. Example:

<node id="VertexColorMaskSlots">
<attribute id="Object" type="FixedString" value="feet" />
</node>

This code would stop the body's feet from loading in and clipping, ideal for boot items. See here for a full list of Vertex Mask Slots for the body.

</children>
</node>
(END OF ITEM MESH)
 </children>
 </node>
</region>	
</save>                          

Materials and Texture .lsx

Now, we move on to our materialbank.

MySweetMod\Public\MySweetMod\Content\Assets\Characters\[PAK]_Armor

I am not reproducing the entire material here, but should be easy enough to find an item material to copy if you search the SourceFile listed.

<?xml version="1.0" encoding="utf-8"?>
 <save>
 	<version major="4" minor="0" revision="4" build="602" />
 (Beginning of materialbank)
 <region id="MaterialBank">
   <node id="MaterialBank">
   <children>
(BEGINNING OF MATERIAL)
<node id="Resource">
<attribute id="DiffusionProfileUUID" type="FixedString" value="" />
<attribute id="ID" type="FixedString" value="00000000000000000000004" /> ID links up to Meshes visualbank.
<attribute id="MaterialType" type="uint8" value="13" />
<attribute id="Name" type="LSString" value="CircletMaterialName" /> Again this is never referenced anywhere else, but it is best to keep it as unique as you can to prevent clashes.
<attribute id="SourceFile" type="LSString" value="Public/Shared/Assets/Materials/Characters/CHAR_BASE.lsf" />
<children>
<node id="ScalarParameters"> x7
(Cut for length)
There should be 4 Texture2DParameters in your material, for BM, NM, PM, and MSK.
<node id="Texture2DParameters">
<attribute id="Enabled" type="bool" value="True" />
<attribute id="ExportAsPreset" type="bool" value="True" />
<attribute id="GroupName" type="FixedString" value="01 Texture Map" />
<attribute id="ID" type="FixedString" value="00000000000000NM" /> This links to texturebank.
<attribute id="ParameterName" type="FixedString" value="normalmap" />
<attribute id="UniformName" type="FixedString" value="Texture2DParameter_normalmap_DefaultWrapSampler" />  These parts tells you what it is.
Look for normalmap, physicalmap, basecolor and MSKColor. We are just going to list the normalmap here.
<node id="Vector3Parameters"> You can use these to set an inherent colour to your material.
<attribute id="BaseValue" type="fvec3" value="0.7667436 0.7667436 0.7667436" />
<attribute id="Enabled" type="bool" value="True" />
<attribute id="ExportAsPreset" type="bool" value="True" />
<attribute id="GroupName" type="FixedString" value="02 Colour" />
<attribute id="IsColor" type="bool" value="True" />
<attribute id="ParameterName" type="FixedString" value="Metal_Primary" /> This one will affect the primary metal of the armour.

<attribute id="Value" type="fvec3" value="1 1 1" /> The 1 1 1 is the colour code here. You can use BG3 Minitool to convert a value.	
</node>

(Cut for length)
</node>
</children>
</node>
(End of material)
(add more materials underneath!)
</children>
</node>
</region>
(End of MaterialBank)

Now the material we have found, SourceFile "Public/Shared/Assets/Materials/Characters/CHAR_BASE.lsf" is a fairly standard shader without transparency or glowing. Materials that can be Transparent have 'Alpha' in the title. For example, "Public/Shared/Assets/Materials/Characters/CHAR_BASE_AlphaTest_2S.lsf" or "CHAR_BASE_AlphaTest_2S_Dither" will enable alpha and make the mesh visible from both sides (turns off backface culling). Underwear needs to have a Dither shader or it won't hide correctly.

Materials with _VT at the end are useless to us, as they only work with virtual texture. A virtualtexture is essentially a box for textures that makes it load faster. We don't have any way of packing virtualtextures ourselves, so do not attempt to use those materials.

In order to make, say, pants disappear when boots are put on, you may need to use a _Vertcut Material, such as 'Public/Shared/Assets/Materials/Characters/CHAR_BASE_VertCut.lsf', and ensure VertexMask is set to True in the mesh lsx. (As well as vertex painting the item itself the desired colour)

We now add a texturebank to the same lsx.

   <region id="TextureBank">
   <node id="TextureBank">
   <children>
   (texture begins here)
   <node id="Resource">
   <attribute id="Name" type="LSString" value="Generated/Public/MySweetMod/Assets/MSW_CoolCirclet_NM" /> The name is never referenced anywhere else but try to keep it unique.
   <attribute id="ID" type="FixedString" value="00000000000000NM" /> This links up to the node in the materialbank!
   <attribute id="SourceFile" type="LSString" value="Generated/Public/MySweetMod/Assets/MSW_CoolCirclet_NM.DDS" /> Capitalisation is IMPORTANT. Make sure your texture is not named MSW_CoolCirclet_NM.dds or it won't load.
   <attribute id="Format" type="uint32" value="64" /> 
   <attribute id="Width" type="int32" value="1024" /> These dimensions don't need to be exact. I believe if it is smaller than listed, the texture will tile.
   <attribute id="Height" type="int32" value="1024" />				
   <attribute id="Depth" type="int32" value="1" />
   <attribute id="Localized" type="bool" value="False" />
   <attribute id="SRGB" type="bool" value="False" /> Ensure this is set to False on anything except a Basecolour! All other maps do not convey colour information so they don't need it on.
   <attribute id="Streaming" type="bool" value="True" />
   <attribute id="Template" type="FixedString" value="" />
   <attribute id="Type" type="int32" value="1" />
   </node>	
   (texture ends here)
   (add more textures underneath!)
   		</children>
           </node>
           </region>	
           </save>

If there is anything wrong with the material, your item may simply refuse to show up, so it is worth double-checking everything here.

RootTemplate

Now for the game to recognise the circlet as an item, we add it to the root template lsx:

MySweetMod\Public\MySweetMod\RootTemplates\MySweetMod.lsf.lsx

<?xml version="1.0" encoding="utf-8"?>
<save>
   <version major="4" minor="0" revision="6" build="5" />
   <region id="Templates">
       <node id="Templates">
           <children> 

(START OF ITEM)
<node id="GameObjects"> Beginning of Circlet item. You may wish to annotate this with a title
<attribute id="Description" type="TranslatedString" handle="HANDLE2" version="1" /> Generate a handle for this in your .loca file.
<attribute id="DisplayName" type="TranslatedString" handle="HANDLE1" version="1" /> Generate a handle for this in your .loca file.
<attribute id="EquipSound" type="FixedString" value="ea27b98e-5fc0-4b0d-8602-e4a421dd481e" /> Not necessary but you may wish to specify one or it will use whatever default sound is in the parent template.
<attribute id="Icon" type="FixedString" value="Item_Cloth_Headwear_Circlet_Silver_A" /> This is a base game icon- custom icons require addition lsx and texture work.
<attribute id="LevelName" type="FixedString" value="" />
<attribute id="MapKey" type="FixedString" value="0000000000000000000000000002" /> This links up to the armor.txt to form the armor.
<attribute id="Name" type="LSString" value="MY_COOL_NEW_CIRCLET" /> This links up to the armor.txt to form the armor.
<attribute id="ParentTemplateId" type="FixedString" value="4d2e0931-3a01-4759-834b-8ae36749daab" /> This tells the game roughly what kind of item it is, such as in this case a helm. You should use the right kind for your item to avoid inherited problems. For example a shield will not know it is a shield without this ParentTemplate.
<attribute id="PhysicsTemplate" type="FixedString" value="327039da-0827-811f-24e8-fc57e86c7ba2" /> I believe similar to the above, this needs to be roughly the same type as the armour you are adding.
<attribute id="Type" type="FixedString" value="item" />
<attribute id="UnequipSound" type="FixedString" value="f4c24367-83af-484e-bcc5-0438b8e64dec" />  Not necessary but you may wish to specify one or it will use whatever default sound is in the parent template.
<attribute id="VisualTemplate" type="FixedString" value="2136f57a-a35f-c2fe-69fb-29afa9ebc8db" /> This is the mesh mapkey to the LOOT model. The LOOT model is the one that appears when you examine it, or throw the item. For a weapon, the LOOT model and the item model are the same. 
<attribute id="_OriginalFileVersion_" type="int64" value="144115207403209032" />
	<children>

If your item is something droppable, it may contain the Bounds node. This tells it the size of the white circle that will appear on interacting with the dropped object.

   <node id="Bounds">
 							<children>
 								<node id="Bound">
 									<attribute id="Height" type="float" value="1" />
 									<attribute id="Max" type="fvec3" value="0.1912984 0.03773662 0.2818625" />
 									<attribute id="Min" type="fvec3" value="-0.1951099 0.001149297 -0.194317" />
 									<attribute id="Radius" type="float" value="0.433013" />
 									<attribute id="Shape" type="uint8" value="1" />
 									<attribute id="Type" type="uint8" value="1" />
 								</node>
 								<node id="Bound">
 									<attribute id="Height" type="float" value="1" />
 									<attribute id="Max" type="fvec3" value="0.1912984 0.03773662 0.2818625" />
 									<attribute id="Min" type="fvec3" value="-0.1951099 0.001149297 -0.194317" />
 									<attribute id="Radius" type="float" value="0.433013" />
 									<attribute id="Shape" type="uint8" value="1" />
 									<attribute id="Type" type="uint8" value="2" />
 								</node>
 								<node id="Bound">
   									<attribute id="Height" type="float" value="1" />
     									<attribute id="Max" type="fvec3" value="0.25 1 0.25" />
 									<attribute id="Min" type="fvec3" value="-0.25 0 -0.25" />
 									<attribute id="Radius" type="float" value="0.2165065" />
 									<attribute id="Shape" type="uint8" value="1" />
 									<attribute id="Type" type="uint8" value="0" />
   								</node>
 							</children>
   						</node>


		<node id="Equipment">
			<children>
				<node id="AfroLongHair" />
				<node id="AfroShortHair" />
				<node id="CurlyLongHair" />
				<node id="CurlyShortHair" />
				<node id="DreadLongHair" />
				<node id="DreadShortHair" />
				<node id="LongHair" />
               
The races Githyanki, Dragonborn and Tiefling are set to automatically use HUM or HUM_STRONG models, unless they are manually opted out by adding this Parentrace node. 
Adding this parentracenode will set the item to use race-specific meshes for any race you specify with its Race UUID. 
You may wish to not bother making a tiefling specific mesh unless there is very obnoxious tail or horn clipping, so you can simply not include them in the parentrace node.
<node id="ParentRace"> 
<children>
<node id="Object">
<attribute id="MapKey" type="guid" value="6503c830-9200-409a-bd26-895738587a4a" /> Tiefling Male
<attribute id="MapValue" type="guid" value="00000000-0000-0000-0000-000000000000" /> This zeroes the race out of the ParentRace node.

</node>
(The other parentrace overrides all removed for length as they all follow the same format - the race UUID and the 0 mapvalue)

</children>
				

</node>
<node id="ShortHair" />
		<node id="Slot">
		<attribute id="Object" type="FixedString" value="Headwear" />
		</node>
	       <node id="Slot">
		<attribute id="Object" type="FixedString" value="Hair" />
			</node>
				<node id="VisualSet">
					<attribute id="BodySetVisual" type="FixedString" value="" />
					<attribute id="ShowEquipmentVisuals" type="bool" value="False" />
					<children>
<node id="MaterialOverrides"> Sets colours for this one specific item, overriding the ones set in the material.
<attribute id="MaterialResource" type="FixedString" value="" />
<children>
<node id="MaterialPresets" />

(We can add any colour available to us (cloth, leather, accent) but this circlet is only metal 1 so we only need to list metal 1.)

<node id="Vector3Parameters">
<attribute id="Color" type="bool" value="False" />
<attribute id="Custom" type="bool" value="True" />
<attribute id="Enabled" type="bool" value="False" />
<attribute id="Parameter" type="FixedString" value="Metal_Primary" />
<attribute id="Value" type="fvec3" value="0.7667436 0.7667436 0.7667436" /> The colour code in Hex form, you can use BG3 Minitool to convert a value.							
</node>
</children>
</node>
<node id="RealMaterialOverrides" />
</children>
</node>


<node id="Visuals">
<children>

<node id="Object">
<attribute id="MapKey" type="guid" value="71180b76-5752-4a97-b71f-911a69197f58" /> Human Male Race IUUD example. Others Here					
<children>
<node id="MapValue">
<attribute id="Object" type="FixedString" value="00000000000000000000000000001" /> Your Mesh for Human Male
</node>
</children>
</node>
(Removed for length - all the other mapkeys/mapvalues of every race this item is available for)
					</children>
				</node>
				<node id="WavyLongHair" />
				<node id="WavyShortHair" />
			</children>
		</node>
	</children>
</node>						
 </node>
(END OF ITEM)
           </children>
       </node>
   </region>
</save>


Armor and Passives

MySweetMod\Public\MySweetMod\Stats\Generated\Data\Armor.txt

MySweetMod\Public\MySweetMod\Stats\Generated\Data\Passive.txt

Meanwhile in your Armor.txt, they link up like this:

You can look at the game’s own armor.txt for ideas of what to put here. You can delete what you don't wish to add, all you really need is the entry, the type, what slot it uses and the RootTemplate.

Armor.txt
new entry "MY_COOL_NEW_CIRCLET"
type "Armor"
data "ValueOverride" "4000" (It's a very cool circlet and we want it to cost a lot!)
data "Weight" "0.01"
using "_Head_Magic_Circlet" (This tells it what slot to equip in. Ideally this should match up with the ParentTemplate you set up.)
data "RootTemplate" "0000000000000000000000000002" Matches up to the rootemplate Mapkey.
data "Rarity" "Rare" This effects what colour it is in your inventory, rarer things get a different colour outline. Note that if you set things as common they may spawn in generic containers, which is not optimal for clean uninstalling.
data "Boosts" "UnlockSpell(Target_MAG_HealingWord);UnlockSpell(Shout_MAG_HealingWord_Mass)" This forces it to give us these spells. Note that the character needs spell slots in able to use them! If you want it for everyone you may be better off setting it up as a custom passive.
data "PassivesOnEquip" "MAG_Radiant_Radiating_Helmet_Passive;CUSTOMPASSIVEIMADE" (The ; seperates passives.)
data "Unique" "1" (These may cause you a headache if you put it multiple places, as they won't spawn for people who overlooked the first one. So I don't recommend using these!)
data "MinAmount" "1"
data "MaxAmount" "1" 

Other using slots include "ARM_Camp_Body", "_Vanity_Shoes_Generic_Common" for camp clothes, "_Foot_Magic" for boots, "ARM_Robe_Body" for robes, "_Hand" for gloves.

If adding a custom passive, your Passive.txt will look like this. You don't need a passive.txt at all, you can make perfectly good items just reusing the game's passives, this is just for the ambitious.

The example passive code is borrowed from Isobel's armor.

new entry "CUSTOMPASSIVEIMADE"
type "PassiveData"
data "DisplayName" "HANDLE3;1" (Generate a handle for this in your .loca file.)
data "Description" "HANDLE4;1" Generate a handle for this in your .loca file.)
data "Icon" "CUSTOMPASSIVEICON" (we can set this up in the same way an item icon is set up)
data "DescriptionParams" "DealDamage(1d4, Radiant)"
data "StatsFunctorContext" "OnAttacked"
data "StatsFunctors" "IF(context.HasContextFlag(StatsFunctorContext.OnAttacked) and HasStatus('MAGE_ARMOR') and IsLastConditionRollSuccess(ConditionRollType.ConditionSavingThrow) and not Self() and IsSavingThrow()):DealDamage(SWAP, 1d4, Radiant,Magical)"

Loca

MySweetMod\Localization\English\MySweetMod.loca.xml

You can generate a handle by ticking the Handle box next to 'GENERATE' on the Multitool. It is much like an UUID but it starts with an H. The version number has to do with internal references. Just make all of yours say 1.

<?xml version="1.0" encoding="utf-8"?><contentList>
<content contentuid="HANDLE1" version="1">Circlet</content> 
<content contentuid="HANDLE2" version="1">My circlet is cool.</content>
<content contentuid="HANDLE3" version="1">Circlet Passive</content> 
<content contentuid="HANDLE4" version="1">While the wearer has Mage Armour, each successful Saving throw causes the source of the Saving Throw to take 1-4 Radiant damage.</content>
</contentList>

TreasureTable

MySweetMod\Public\MySweetMod\Stats\Generated\TreasureTable.txt

Now, you need to put it in the treasuretable.

Your treasuretable should look like this:

new treasuretable "TUT_Chest_Potions"
CanMerge 1
new subtable "1,1"
object category "I_MY_COOL_NEW_CIRCLET",1,0,0,0,0,0,0,0

This will make it spawn in the tutorial chest. Other treasuretable codes to put it different places can be found here- Modder's Resource - Treasure Table Spreadsheet.

Make sure you don't forget the I_ prefix for the item!

The numbers affect the drop rate chance among other things. The numbers above will cause the item to always spawn in the chest. For more info see Larian's wiki page on TreasureTables, it is for a different game but shares the same idea.

If you plan to put a lot of items in your mod, it is recommended to create a bag item containing them and put that in the Tutorial Chest, to avoid clutter.

If something goes wrong, it is recommended to overwrite a custom mesh from someone else's mod, or add it to the back of an existing mod. When you know the fault is not with your mesh, you check your materials, and so you can fix things one step at a time.