Cool game! i like the whole level design and the gradually growing maze, it really helps with not getting people confused and overwhelmed. It was fun to move around, and the ghost thing really caught me offguard. But something i found a little boring and confusing, was that i had no idea where the keys were, so i just walked around blindly, and didn't know if i made progress or not. I recommend adding an indicator or arrow showing where the keys are, so it's a little less confusing.
But other than that, great game!