I didn't quite get the color changing thing for a bit, but once I understood it it was pretty fun :) really liked the intro / tutorial as well, that was clean.
Glad you liked the tutorial/intro ... was more of a last-minute addition. Had a more elaborate tutorial in mind, but ditched that due to time-constraints.
The color changing is something to "get", indeed. Would've liked it more if I could've explained it more clearly.
