I like the concept and level design. The puzzles were interesting because it seems like there were often more than one way to beat them. If you keep working on this one, I'd suggest tweaking the physics to feel a bit less heavy/unpredictable and maybe making some of the puzzles a bit easier - I had a few where I accidentally pushed a box off a ledge and then felt like I couldn't beat the puzzle. But, overall, nicely done :)