Checking Bool freezes UE4 - bug or issue on my end?

I can’t check the state of a bool in my third person BP from an actor in the level. It freezes UE4 - not crash, but freezes. All sound effects persist, screen freezes, no input.

Here’s an image. The portions in the orange box are causing the freeze - when I remove them, it works just find. The top portion works fine actually when I remove the Set bool portions in the bottom image.