Able Ability System Info and Support Thread

That looks like you aren’t passing an Ability Component (or possibly an Ability) properly when you call Activate Ability and pass in the Ability Context. I’d check your code there and see if anything is null.

Nope. I use 4.18 personally. Are you talking about the Preview Actor Selection Box? Check and make sure you are picking a class you actually have some assets of (such as Actor), or you can not pick a class and it should load everything.