Testing Mod Error

[Oblit]

I'm trying to make some tests with my alien race mod but I've been getting some errors that I don't know what exactly they are

I'm using Harmony + Hugslib + AlienRaces + MyMod
The error only occurs when I put MyMod

Is it maybe because I'm forgetting some required alienrace folder?
Thats the only thing I could think of since I wanted to test once before finishing all the code

Thank you for your help in advance!

Here is the error log
================================================================================================
Could not execute post-long-event action. Exception: System.InvalidOperationException: Sequence contains no elements
  at System.Linq.Enumerable.First[TSource] (System.Collections.Generic.IEnumerable`1[T] source) [0x00010] in <351e49e2a5bf4fd6beabb458ce2255f3>:0
  at RimWorld.GenStuff.DefaultStuffFor (Verse.BuildableDef bd) [0x00136] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.ThingDef.ResolveIcon () [0x00070] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.BuildableDef.<PostLoad>b__58_0 () [0x00020] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.LongEventHandler.ExecuteToExecuteWhenFinished () [0x0007d] in <7927e938de4c4089b4add4215e58d5b1>:0
Verse.Log:Error(String, Boolean)
Verse.LongEventHandler:ExecuteToExecuteWhenFinished()
Verse.LongEventHandler:UpdateCurrentAsynchronousEvent()
Verse.LongEventHandler:LongEventsUpdate(Boolean&)
Verse.Root:Verse.Root.Update_Patch1(Root)
Verse.Root_Entry:Update()


Could not execute post-long-event action. Exception: System.InvalidOperationException: Sequence contains no elements
  at System.Linq.Enumerable.First[TSource] (System.Collections.Generic.IEnumerable`1[T] source) [0x00010] in <351e49e2a5bf4fd6beabb458ce2255f3>:0
  at RimWorld.GenStuff.DefaultStuffFor (Verse.BuildableDef bd) [0x00136] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.ThingDef.ResolveIcon () [0x00070] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.BuildableDef.<PostLoad>b__58_0 () [0x00020] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.LongEventHandler.ExecuteToExecuteWhenFinished () [0x0007d] in <7927e938de4c4089b4add4215e58d5b1>:0
Verse.Log:Error(String, Boolean)
Verse.LongEventHandler:ExecuteToExecuteWhenFinished()
Verse.LongEventHandler:UpdateCurrentAsynchronousEvent()
Verse.LongEventHandler:LongEventsUpdate(Boolean&)
Verse.Root:Verse.Root.Update_Patch1(Root)
Verse.Root_Entry:Update()


Could not execute post-long-event action. Exception: System.InvalidOperationException: Sequence contains no elements
  at System.Linq.Enumerable.First[TSource] (System.Collections.Generic.IEnumerable`1[T] source) [0x00010] in <351e49e2a5bf4fd6beabb458ce2255f3>:0
  at RimWorld.GenStuff.DefaultStuffFor (Verse.BuildableDef bd) [0x00136] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.ThingDef.ResolveIcon () [0x00070] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.BuildableDef.<PostLoad>b__58_0 () [0x00020] in <7927e938de4c4089b4add4215e58d5b1>:0
  at Verse.LongEventHandler.ExecuteToExecuteWhenFinished () [0x0007d] in <7927e938de4c4089b4add4215e58d5b1>:0
Verse.Log:Error(String, Boolean)
Verse.LongEventHandler:ExecuteToExecuteWhenFinished()
Verse.LongEventHandler:UpdateCurrentAsynchronousEvent()
Verse.LongEventHandler:LongEventsUpdate(Boolean&)
Verse.Root:Verse.Root.Update_Patch1(Root)
Verse.Root_Entry:Update()
================================================================================================

[RawCode]

you have "stuff" object without "stuff" declaration

this is xml (data) issue and not related to your code