The simple graphics made the game run super-smoothly. The controls were simple, so it was easy to wrap my mind around the puzzles once I got into the rhythm. The difficulty incline wasn't too harsh. Relaxing music instead of "retro" techno. With the way it's presented, and especially the last level, I feel like it might have meant something when the two shapes collided all from how you conveyed their relationship. The game itself was a little challenging, but I use that word sparingly because there's a difference between challenging and just hard. This game is not unbeatable which makes it all the more lovable.
Over all, the only bad thing, which isn't really that bad, is the shortness of the game. But you were doing this for LD, which in my opinion is a terrible idea in itself because you can't make a complete game with good quality and decent length in just two days. That is, unless you're on crack and don't sleep, in which case you might fuck up your game. Anyway, good shot at it.