I really like the puzzles, I had fun solving them. The game mechanic seemed weak at first, but level design was so genius it actually amplified its fun a lot. It's one of those games where the game mechanic goes hand in hand with level design. I love it.
You really made me think hard on some puzzles. And I especially like the last level! You really have to think out of the box *wink* :)
Overall a really impressive game. I could see this winning the jam. Bravo.