This was really fun, I'd say it's too short. But when you're having fun and the game is good, you're gonna want more, so good work.
The controls and physics are extremely good, brilliant use of only one button to create rules that work.
Good work implementing new things, puzzle games sometimes spend way to long on one system before introducing another, or they throw too much at you too quickly, so again, good job.
Music and sounds work well, the sounds are satisfying when you get stuff done, particularly the key and unlocking door ones.