REFERENCE ITEM:
    item JacketLong_DesperadoOPEN
    {
        DisplayCategory = Clothing,
        Type = Clothing,
        DisplayName = Leather Jacket,
        ClothingItem = JacketLong_DesperadoOPEN,
        BodyLocation = Jacket,
        Icon = JacketLongBlack,
        BloodLocation = LongJacket,
        RunSpeedModifier = 0.93,
        CombatSpeedModifier = 0.97,
        BiteDefense = 20,
        ScratchDefense = 40,
        NeckProtectionModifier = 0.5,
        FabricType = Leather,
        Weight = 2,
        WorldStaticModel = JacketLong_Ground,
        ClothingItemExtra = MFTEOTW.JacketLong_Desperado,
        ClothingItemExtraOption = CloseJacket,
        clothingExtraSubmenu = OpenJacket,
    }

RESULT:
    item JacketLong_OutlawOPEN
    {
        DisplayCategory = Clothing,
        Type = Clothing,
        DisplayName = Leather Jacket,
        ClothingItem = JacketLong_OutlawOPEN,
        BodyLocation = Jacket,
        Icon = JacketLongBrown,
        BloodLocation = LongJacket,
        RunSpeedModifier = 0.93,
        CombatSpeedModifier = 0.97,
        BiteDefense = 20,
        ScratchDefense = 40,
        NeckProtectionModifier = 0.5,
        FabricType = Leather,
        Weight = 2,
        WorldStaticModel = JacketLong_Ground,
        ClothingItemExtra = MFTEOTW.JacketLong_Outlaw,
        ClothingItemExtraOption = CloseJacket,
        clothingExtraSubmenu = OpenJacket,
    }

THEN:
- COPY EXISTING FUNCTIONAL XMLS AND RENAME
- GENERATE NEW GUIDS AND INSERT INTO NEW XMLS
- REGISTER NEW GUIDS AND XMLS INTO FILEGUIDTABLE

RESULT:
ERROR: General     , 1751782403056> ExceptionLogger.logException> Exception thrown java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null at AnimationPlayer.getSkinningBoneIndex line:340.
ERROR: General     , 1751782403056> DebugLogStream.printException> Stack trace:
java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null
	at zombie.core.skinnedmodel.animation.AnimationPlayer.getSkinningBoneIndex(AnimationPlayer.java:340)
	at zombie.core.skinnedmodel.ModelManager.newStaticInstance(ModelManager.java:1801)
	at zombie.core.skinnedmodel.population.PopTemplateManager.addClothingItem(PopTemplateManager.java:113)
	at zombie.core.skinnedmodel.population.PopTemplateManager.populateCharacterModelSlot(PopTemplateManager.java:250)
	at zombie.core.skinnedmodel.ModelManager.DoCharacterModelParts(ModelManager.java:1234)
	at zombie.core.skinnedmodel.ModelManager.Reset(ModelManager.java:640)
	at zombie.core.skinnedmodel.ModelManager.update(ModelManager.java:1247)
	at zombie.gameStates.IngameState.updateInternal(IngameState.java:1698)
	at zombie.gameStates.IngameState.update(IngameState.java:1333)
	at zombie.gameStates.GameStateMachine.update(GameStateMachine.java:101)
	at zombie.GameWindow.logic(GameWindow.java:298)
	at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:71)
	at zombie.GameWindow.frameStep(GameWindow.java:765)
	at zombie.GameWindow.run_ez(GameWindow.java:681)
	at zombie.GameWindow.mainThread(GameWindow.java:495)
	at java.base/java.lang.Thread.run(Unknown Source)
ERROR: General     , 1751782403062> ExceptionLogger.logException> Exception thrown java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null at AnimationPlayer.getSkinningBoneIndex line:340.
ERROR: General     , 1751782403062> DebugLogStream.printException> Stack trace:
java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null
	at zombie.core.skinnedmodel.animation.AnimationPlayer.getSkinningBoneIndex(AnimationPlayer.java:340)
	at zombie.core.skinnedmodel.ModelManager.newStaticInstance(ModelManager.java:1801)
	at zombie.core.skinnedmodel.population.PopTemplateManager.addClothingItem(PopTemplateManager.java:113)
	at zombie.core.skinnedmodel.population.PopTemplateManager.populateCharacterModelSlot(PopTemplateManager.java:250)
	at zombie.core.skinnedmodel.ModelManager.DoCharacterModelParts(ModelManager.java:1234)
	at zombie.core.skinnedmodel.ModelManager.Reset(ModelManager.java:640)
	at zombie.core.skinnedmodel.ModelManager.update(ModelManager.java:1247)
	at zombie.gameStates.IngameState.updateInternal(IngameState.java:1698)
	at zombie.gameStates.IngameState.update(IngameState.java:1333)
	at zombie.gameStates.GameStateMachine.update(GameStateMachine.java:101)
	at zombie.GameWindow.logic(GameWindow.java:298)
	at zombie.core.profiling.AbstractPerformanceProfileProbe.invokeAndMeasure(AbstractPerformanceProfileProbe.java:71)
	at zombie.GameWindow.frameStep(GameWindow.java:765)
	at zombie.GameWindow.run_ez(GameWindow.java:681)
	at zombie.GameWindow.mainThread(GameWindow.java:495)
	at java.base/java.lang.Thread.run(Unknown Source)
ERROR: General     , 1751782403067> ExceptionLogger.logException> Exception thrown java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null at AnimationPlayer.getSkinningBoneIndex line:340.
ERROR: General     , 1751782403067> DebugLogStream.printException> Stack trace:
java.lang.NullPointerException: Cannot invoke "java.lang.Integer.intValue()" because the return value of "java.util.HashMap.get(Object)" is null