Had a new crash problem that I feel like probably stems from the same underlying issues with custom structs so I’ll post it here: same project. On any class blueprint (even a completely empty one), make a new variable which is an array of Rooms. This works fine while you’re in the editor, whatever you might be doing with it, but if, by default, the array actually contains any Rooms, saving the blueprint will cause the editor to crash.
Leaving the array empty by default, but making it an editable var and adding to the array on an instance of your actor in the level will also cause a crash on save.
Basically, array of Rooms being nonzero = crash on save, but I don’t think there’s anything wrong with the struct itself.