It throws a NullReferenceException during ReadingPolicyDatabase.GenerateStartingPolicies(), which prevents the game from getting past the scenario screen.

None of the XMLs mention reading policies directly, so I suspect there may be an ingestible item or ThingDef missing a required class or stat — like drugCategory, ingestible, or a broken statBase entry.

If it helps, the exact log line is:
Exception filling window for RimWorld.Page_SelectScenario: System.NullReferenceException at RimWorld.ReadingPolicyDatabase.GenerateStartingPolicies()


I did not write this up, I am still trying to figure exactly what mod is causing your mod to not let me past the Scenario selection. But I wanted to go ahead and drop this so you could look at what Chatgpt said (I am not a coder so I use it for help). I'm like quite certain it's a conflict on my end. But like I said, I wanted to post this and see if you can either do anything with the information above, or if that's useless just tell me and I'll keep trying to figure out what mod's causing the conflict.