Init robotWorkTypes - Count:1
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Warning (string)
AIRobot.X2_AIRobot_Pawn_WorkSettings:EnableAndInitialize ()
AIRobot.X2_AIRobot_Pawn_WorkSettings:.ctor (Verse.Pawn)
System.Reflection.MonoCMethod:InternalInvoke (object,object[])
System.Reflection.MonoCMethod:DoInvoke (object,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
System.Reflection.MonoCMethod:Invoke (System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo)
System.RuntimeType:CreateInstanceImpl (System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo,object[],System.Threading.StackCrawlMark&)
System.Activator:CreateInstance (System.Type,System.Reflection.BindingFlags,System.Reflection.Binder,object[],System.Globalization.CultureInfo,object[])
System.Activator:CreateInstance (System.Type,object[])
Verse.ScribeExtractor:SaveableFromNode<RimWorld.Pawn_WorkSettings> (System.Xml.XmlNode,object[])
Verse.Scribe_Deep:Look<RimWorld.Pawn_WorkSettings> (RimWorld.Pawn_WorkSettings&,bool,string,object[])
Verse.Scribe_Deep:Look<RimWorld.Pawn_WorkSettings> (RimWorld.Pawn_WorkSettings&,string,object[])
(wrapper dynamic-method) Verse.Pawn:Verse.Pawn.ExposeData_Patch3 (Verse.Pawn)
AIRobot.X2_AIRobot:ExposeData ()
Verse.ScribeExtractor:SaveableFromNode<Verse.Thing> (System.Xml.XmlNode,object[])
Verse.Scribe_Collections:Look<Verse.Thing> (System.Collections.Generic.List`1<Verse.Thing>&,bool,string,Verse.LookMode,object[])
Verse.Scribe_Collections:Look<Verse.Thing> (System.Collections.Generic.List`1<Verse.Thing>&,string,Verse.LookMode,object[])
(wrapper dynamic-method) Verse.Map:Verse.Map.ExposeData_Patch1 (Verse.Map)
Verse.ScribeExtractor:SaveableFromNode<Verse.Map> (System.Xml.XmlNode,object[])
Verse.Scribe_Collections:Look<Verse.Map> (System.Collections.Generic.List`1<Verse.Map>&,bool,string,Verse.LookMode,object[])
Verse.Scribe_Collections:Look<Verse.Map> (System.Collections.Generic.List`1<Verse.Map>&,string,Verse.LookMode,object[])
(wrapper dynamic-method) Verse.Game:Verse.Game.LoadGame_Patch3 (Verse.Game)
(wrapper dynamic-method) Verse.SavedGameLoaderNow:Verse.SavedGameLoaderNow.LoadGameFromSaveFileNow_Patch1 (string)
Verse.Root_Play/<>c:<Start>b__1_1 ()
Verse.LongEventHandler:RunEventFromAnotherThread (System.Action)
Verse.LongEventHandler/<>c:<UpdateCurrentAsynchronousEvent>b__27_0 ()
System.Threading.ThreadHelper:ThreadStart_Context (object)
System.Threading.ExecutionContext:RunInternal (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,bool)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object)
System.Threading.ThreadHelper:ThreadStart ()

Those error messages disappeared after I removed all the robots.
Log
https://gist.github.com/db7c86f7ce646aaa0426fd1d4b3b1c69