My feedback is almost identical to Exco's: lovely atmosphere, dynamic music is terrific, love the core concept. Just didn't feel the most natural control-wise, and I also had trouble telling when I wasn't placing an object on something solid. I also got soft-locked on the third level (one star), hit the bell and "3" showed up but never counted down.
Great work by the entire team, it's a super cool concept/world that I'd love to see polished up more!