This was a great puzzle game. There are certainly nitpicks, most of which it looks like other people have already pointed out. I guess I can say that sometimes it felt like there wasn't an "aha" moment like in some other puzzle games, but instead found myself just kind of almost randomly moving the blocks and hoping that would be the solution - sometimes the solutions are very chaotic (especially with the purple blocks), and I don't really see how I was supposed to logic those levels out without basically guess-and-check. Maybe a "replay animation" button after you beat the level would help with that, because then you can really focus on what happens with the blocks the second time you see it?
But still, again, this is nitpicking. The overall concept, presentation, and execution were all very well done.