I had a lot of fun playing this. The music was nice, the art looked good (other than the default Unity skybox :P), and the game fit the theme well. Also, the idea was pretty novel, and it was executed very well for the most part. I had to play the WebGL version because everything except for the main menu was black on the Mac version. Also a different button than escape for pause would be nice, at least on the WebGL version, because escape exits fullscreen on WebGL. On the green level, I'm not sure if I did the pulley thing the intended way. I pushed the box into the left platform and quickly jumped to the one on the right to get the key. Something about that felt kind of weird. Other than those issues, I had a lot of fun solving the puzzles, and beat the game with 3 minutes left on my second run.