note: see reference to class template instantiation 'TArray' being compiled

Hi UnrealEverything,
that is the whole error I’m afraid…
You are right about the ampersand, it slipped in there in one of the various attempts to make the code work.
Room is a c++ native struct.

EDIT: worth to mention that IntelliSense doesn’t highlight anything, the error is when trying to compile from UE
EDIT2: I think you are onto something there with prefixes, could you elaborate it a bit please?
EDIT3: correct syntax provided in the AnswerHUB