Cool game, the minimalist design was very aesthetically pleasing!
I think I found an unintended mechanic caused by the physics engine where you can stick to/jump up walls. I'm not sure if it was intended or not though because I don't know how I would have beaten the levels without using it. I'm not really sure about the puzzle aspect of the game because it seemed like the play was always to make a beeline for the goal with each cube. I might be missing something here.