I know that the ability system is created, and i’ve followed along with the rest of the initialization in begin play which works fine. I can also use try activate ability by class on the ability system, which works fine.
Do you have an enum in your game called AbilityInput that is marked with UENUM? If not, then the ability system will crash when attempting to access that enum.
I don’t believe that the reflection system will pick up on enums defined in CPP files. If you move that enum to a header, do you still get the crash? (Also, as a side note, enums in Unreal are supposed to begin with E.)