Very nice! The puzzles were challenging, which is good. I also liked the way you used text in the levels to introduce new mechanics. tutorials are often overlooked. I love the retro style of the game. The window was a bit small tho. Maybe thats something to look into.
I received some complaints when it was at the larger size. The downloadable version on the LD website is twice the size, but I was not consider scaling when I made it and anything other than that would require code changes, which would be against the rules of the competition, but I know this is something I need to think more about in the future!