Pretty good puzzle game here, though a few points to consider.
1: Music is nice, but it gets stale after a while. Would have been cool to have a unique music track for each world.
2: A good number of the puzzles were nice and brain-twisting, but a lot of them, particularly in the later half of the game, kind of just solve themselves after you fiddle around just a little. I accidentally solved a bunch on the first try just by moving at a whim. What I'd suggest doing if you make a sequel or another puzzle game is to have your levels playtested by a bunch of different folks and then sort them in order of how difficult it was for people to solve them.
3: You should make muting the music and sound separate buttons. I turned off the music after a while, but I didn't want to also turn off the sound effects.
Overall, good work. I'd like to see more puzzle games from you in future.