I really liked this game. Interesting, nice concept, new game flow. I would like to see more of this or an extended version. I echo some of the others' statements... it took a little while to figure out how to work the mirror pieces, but that was more a limitation to what I thought the mirror did. I was assuming the mirror side was on the outside of the cube it was being placed on, not the inside.
Great game, soothing music... there was a mute option, but I didn't need it :)
ps - I'm glad I didn't have to lug different pieces from room to room... but I can see where that could have been a part of the gameplay (unlocking pieces to use in other areas of the "world")