Wow, I really really had fun with this game. Everything about it is great, the art was great, the audio was nice, and even the presentation was great, it started really nicely with a small backstory. It would probably a really great game if there were more mechanics, but for this game jam, it was really great.
As for the limitation, I think it respects the limitation, I can't say it has more than one level, because the rooms depend on each other. After you unlock something, you have to return to the other rooms to get the keys.