I get this crash whenever I paste a blueprint with a combinator in it. I conjecture, but didn't test, that this only happens if the blueprint doesn't have Blueprint Variables variables in it. I'm really sorry, but I don't have the time, energy, or willpower to investigate this further. I know this isn't very useful. I'm sorry.

e: This is the blueprint I was trying to place, so if it's not a conflict with vanilla, it's a conflict with one of the mods in the blueprint.

+1

In this case, there is an incompatibility with Circuit HUD V2 "hud-combinators". It looks that mod uses a constant combinator type with no parameters. I didn't realize this was possible and thus the error when my mod tries to access the parameters.

I wrapped it in a type check, and it prevents the crash. Unfortunately I don't know how the Circuit HUD V2 mod is not using parameters to store the "Filtered" section and thus my mod can't update them. I'll work on getting my fix published because any combinator mod with no parameters will cause this crash.