If you beat a level and go back to the level select screen, the next level won't be unlocked. Also, you might want to give some kind of hint that bullets can break square glass into a triangle. Other than that, nice game!
If you're stuck on 1-3, make sure the distance between each note in a pair is right (1 empty space between the 1st pair, 1 between the 2nd, 2 between the 3rd and 2 between the 4th) For some reason the distance sometimes changes on you when you move them. If they're not spaced right, it's impossible. I had to refresh to get it right. Other than that, I liked the game.
There's no newer version of the game anywhere (even the developer's website), but you can still join and create games by not clicking "ok" on the error message that pops up. Unfortunately, I think that this is going to make even less people play than before.
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