on world gen only one faction base will spawn, period, and the faction menu remains blank, using the Dev logs I found it comes from this mod I believe. here is the log report
Error in WorldGenStep: System.NullReferenceException: Object reference not set to an instance of an object
at genebodysize.HarmonyPatches+VariedBodySizesModSettings_AffectMeleeDamagePatch.Postfix (VariedBodySizes.VariedBodySizesModSettings& __result) [0x00021] in <0d4aee43d37644fd8eb9a795f768a6ea>:0
at (wrapper dynamic-method) VariedBodySizes.VariedBodySizesMod.VariedBodySizes.VariedBodySizesMod.get_Settings_Patch1(VariedBodySizes.VariedBodySizesMod)
at VariedBodySizes.Pawn_BodySize.Postfix (System.Single& __result, Verse.Pawn __instance) [0x00000] in <4b1cf93a2d5a42b4bffc46eae2292f84>:0
at (wrapper dynamic-method) Verse.Pawn.Verse.Pawn.get_BodySize_Patch1(Verse.Pawn)
at RimWorld.StatPart_BodySize+<>c.<TryGetBodySize>b__2_0 (Verse.Pawn x) [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.PawnOrCorpseStatUtility.TryGetPawnOrCorpseStat (RimWorld.StatRequest req, System.Func`2[T,TResult] pawnStatGetter, System.Func`2[T,TResult] pawnDefStatGetter, System.Single& stat) [0x00019] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.StatPart_BodySize.TryGetBodySize (RimWorld.StatRequest req, System.Single& bodySize) [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.StatPart_BodySize.TransformValue (RimWorld.StatRequest req, System.Single& val) [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.StatWorker.FinalizeValue (RimWorld.StatRequest req, System.Single& val, System.Boolean applyPostProcess) [0x00022] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.StatWorker.GetValue (RimWorld.StatRequest req, System.Boolean applyPostProcess) [0x0004c] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) RimWorld.StatWorker.RimWorld.StatWorker.GetValue_Patch1(RimWorld.StatWorker,Verse.Thing,♥♥♥♥,int)
at (wrapper dynamic-method) RimWorld.StatExtension.RimWorld.StatExtension.GetStatValue_Patch2(Verse.Thing,RimWorld.StatDef,♥♥♥♥,int)
at RimWorld.Pawn_NeedsTracker.SetInitialLevels () [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at Verse.PawnGenerator.TryGenerateNewPawnInternal (Verse.PawnGenerationRequest& request, System.String& error, System.Boolean ignoreScenarioRequirements, System.Boolean ignoreValidator) [0x000e8] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) Verse.PawnGenerator.Verse.PawnGenerator.GenerateNewPawnInternal_Patch1(Verse.PawnGenerationRequest&)
at Verse.PawnGenerator.GenerateOrRedressPawnInternal (Verse.PawnGenerationRequest request) [0x00188] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) Verse.PawnGenerator.Verse.PawnGenerator.GeneratePawn_Patch2(Verse.PawnGenerationRequest)
at RimWorld.Faction.TryGenerateNewLeader () [0x00254] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.FactionGenerator.NewGeneratedFaction (RimWorld.FactionGeneratorParms parms) [0x001f0] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) RimWorld.FactionGenerator.RimWorld.FactionGenerator.GenerateFactionsIntoWorld_Patch0(System.Collections.Generic.List`1<RimWorld.FactionDef>)
at RimWorld.Planet.WorldGenStep_Factions.GenerateFresh (System.String seed) [0x00005] in <1ea541f48818430abd724fc665f76dc4>:0
at RimWorld.Planet.WorldGenerator.GenerateWorld (System.Single planetCoverage, System.String seedString, RimWorld.Planet.OverallRainfall overallRainfall, RimWorld.Planet.OverallTemperature overallTemperature, RimWorld.Planet.OverallPopulation population, System.Collections.Generic.List`1[T] factions, System.Single pollution) [0x0010e] in <1ea541f48818430abd724fc665f76dc4>:0
UnityEngine.StackTraceUtility:ExtractStackTrace ()
Verse.Log:Error (string)
RimWorld.Planet.WorldGenerator:GenerateWorld (single,string,RimWorld.Planet.OverallRainfall,RimWorld.Planet.OverallTemperature,RimWorld.Planet.OverallPopulation,System.Collections.Generic.List`1<RimWorld.FactionDef>,single)
RimWorld.Page_CreateWorldParams:<CanDoNext>b__19_0 ()
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,♥♥♥♥)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object,♥♥♥♥)
System.Threading.ExecutionContext:Run (System.Threading.ExecutionContext,System.Threading.ContextCallback,object)
System.Threading.ThreadHelper:ThreadStart ()

@Wolfstrike Thanks for the report. Can you include a hugslib log generated when you hit the error? It'll help narrow things down.

I tried to use the keybinding shown but it didn't work, and now my game is working and not throwing the error anymore, I disabled and re enabled the mods and kept switching them around and I guess something clicked into place and I cannot replicate the error

Doesnt seem like this mod, but also isnt anything that I can clearly see affects genes. Tries to patch animals, mechs, and animal corpses. Also the log doesnt post for whatever reason, im assuming bc these errors are continuously happening.

Exception drawing Boomalope335010: System.NullReferenceException: Object reference not set to an instance of an object
at Verse.PawnRenderer.DrawBodyGenes (UnityEngine.Vector3 rootLoc, UnityEngine.Quaternion quat, System.Single angle, Verse.Rot4 bodyFacing, Verse.RotDrawMode bodyDrawType, Verse.PawnRenderFlags flags) [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) Verse.PawnRenderer.Verse.PawnRenderer.RenderPawnInternal_Patch3(Verse.PawnRenderer,UnityEngine.Vector3,single,♥♥♥♥,Verse.Rot4,Verse.RotDrawMode,Verse.PawnRenderFlags)
at (wrapper dynamic-method) Verse.PawnRenderer.Verse.PawnRenderer.RenderPawnAt_Patch3(Verse.PawnRenderer,UnityEngine.Vector3,System.Nullable`1<Verse.Rot4>,♥♥♥♥)
at Verse.Pawn_DrawTracker.DrawAt (UnityEngine.Vector3 loc) [0x00000] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) Verse.Pawn.Verse.Pawn.DrawAt_Patch1(Verse.Pawn,UnityEngine.Vector3,♥♥♥♥)
at Verse.Thing.Draw () [0x00015] in <1ea541f48818430abd724fc665f76dc4>:0
at (wrapper dynamic-method) Verse.ThingWithComps.Verse.ThingWithComps.Draw_Patch1(Verse.ThingWithComps)
at (wrapper dynamic-method) Verse.DynamicDrawManager.Verse.DynamicDrawManager.DrawDynamicThings_Patch1(Verse.DynamicDrawManager)
UnityEngine.StackTraceUtility:ExtractStackTrace ()
(wrapper dynamic-method) Verse.Log:Verse.Log.Error_Patch2 (string)
(wrapper dynamic-method) Verse.DynamicDrawManager:Verse.DynamicDrawManager.DrawDynamicThings_Patch1 (Verse.DynamicDrawManager)
(wrapper dynamic-method) Verse.Map:Verse.Map.MapUpdate_Patch2 (Verse.Map)
(wrapper dynamic-method) Verse.Game:Verse.Game.UpdatePlay_Patch2 (Verse.Game)
Verse.Root_Play:Update ()

with this new update it seems like some incompatibilities formed.
With Gradient Hair, anyone with a gradient gets an error and the famous pink square.
https://gist.github.com/HugsLibRecordKeeper/e577a2ad1d745bbfc9bfe8f6bd7018a8

also it seems that body proportions are out of wack as of now. in a heavily modded game my colossus gene colonist had giant heads and regular bodies, and smaller genes only had their bodies shrink but not their hair.

even during the testing above those colonists sizes increased but not their heads.
i unfortunately can't find errors for those.

I'm having the same problem as Superburns, where my pawns with various different sizes are shown as normal sized pawns with either comically large bobble heads; large hair and beards, or tiny hair and beards.

https://gist.github.com/b8e25120a55296c02317acbeb2352ce8

I'm running a fairly heavy mod list, but recently done a wipe. I am unsure of what could really be the source of the pawns not being their intended size, but I'd like to not get rid of this nice gene mod.

@Superburns I've sent a fix to the gradient hair author, it'll be up as soon as he gets a look at it.

@GrandisimoBull I'll look into it. There's definitely a mod causing some of my changes to fail - see the messages about the variedbodysizes transpiler not finding a target. If you have a chance to cut the list of suspects down, I would appreciate it.

aaand it's combat extended. I'll try to support it but to be honest I'm not excited about the prospect.

Good news, it's not combat extended. It's specifically when both Yayo's Animation and HAR are active.

im getting the same problem as Wolfstirke https://gist.github.com/ef37c4cf60460751317699ec3a0db21a

fixed it moved it toward the bottom of the mod list as the fallowing

Varied body sizes
Body size genes
Humanoid aliens