Hi, me again. I loaded up my mod list to discover that in a new game, the trade-in screen threw an exception. After a bit of testing, I've narrowed it down to the Androids mod. Removing this mod makes things go normally. Here's the exception it throws when the Androids mod is in my modlist:

Exception while generating thing set: System.NullReferenceException: Object reference not set to an instance of an object
at Androids.DroidUtility.MakeDroidTemplate (Verse.PawnKindDef pawnKindDef, RimWorld.Faction faction, System.Int32 tile, System.Collections.Generic.List`1[T] skills, System.Int32 defaultSkillLevel) [0x0018f] in <05e753b882c441eb86b6641f444753b2>:0
at Androids.HarmonyPatches.Patch_PawnGenerator_TryGenerateNewPawnInternal (Verse.Pawn& __result, Verse.PawnGenerationRequest& request, System.String& error) [0x00031] in <05e753b882c441eb86b6641f444753b2>:0
at (wrapper dynamic-method) Verse.PawnGenerator.Verse.PawnGenerator.TryGenerateNewPawnInternal_Patch2(Verse.PawnGenerationRequest&,string&,bool,bool)
at Verse.PawnGenerator.GenerateNewPawnInternal (Verse.PawnGenerationRequest& request) [0x00096] in <c36f9493c9844ddaa7fb5c788416098f>:0
at Verse.PawnGenerator.GenerateOrRedressPawnInternal (Verse.PawnGenerationRequest request) [0x00183] in <c36f9493c9844ddaa7fb5c788416098f>:0
at (wrapper dynamic-method) Verse.PawnGenerator.Verse.PawnGenerator.GeneratePawn_Patch2(Verse.PawnGenerationRequest)
at Rimdeed.StockGenerator_Pawns+<GenerateThings>d__0.MoveNext () [0x0013f] in <d9d59746c4e84fcca0a3d18497a1a84d>:0
at RimWorld.ThingSetMaker_TraderStock.Generate (RimWorld.ThingSetMakerParams parms, System.Collections.Generic.List`1[T] outThings) [0x000e5] in <c36f9493c9844ddaa7fb5c788416098f>:0
at RimWorld.ThingSetMaker.Generate (RimWorld.ThingSetMakerParams parms) [0x00019] in <c36f9493c9844ddaa7fb5c788416098f>:0
Verse.Log:Error(String, Boolean)
RimWorld.ThingSetMaker:Generate(ThingSetMakerParams)
Rimdeed.PawnTrader:GenerateThings(Pawn)
Rimdeed.PawnTrader:StartTrade(Pawn)
Rimdeed.<>c__DisplayClass13_0:<.ctor>b__3()
Verse.DiaOption:Activate()
Rimdeed.GUIHelper:OptOnGUI(DiaOption, Rect, Boolean)
Rimdeed.Dialog_RimDeed_TradePage:DoWindowContents(Rect)
Verse.Window:InnerWindowOnGUI(Int32)
UnityEngine.GUI:CallWindowDelegate(WindowFunction, Int32, Int32, GUISkin, Int32, Single, Single, GUIStyle)