Great idea, had fun playing it. I agree with some of the suggestions from the comments, but another thing I wanted to mention is that I thought the level would not load because I kept pressing space and enter and nothing happened, until I looked up the game page and saw that I should have been pressing z.

A good concept and with good level design. Like other people have said the physics hold it back a little bit, but for a 48 hour gamejam, it's to be expected. I think it's worth working on after the game-jam. With some more work and polish it would be a decently fun game :) 

I love the concept so much! The only thing that holds it back is the physics/collision detection getting in the way and things like the box movement style making it too easy to accidentally push a box into a wall and have to totally reset. I would love to play a nicer version of all of these puzzles!