Valderra: it's a matching game. (It was hard for me, too. I suck at memory games.)
Here's a hint for the white room: the solution lies in all the other rooms.
By the way, have any of you guys tried this one?
EDIT by Admin: Nice new family friendly URL found:
http://www.corwin.ca/gridlock/
I got stuck on stage 13 for a few days. After that, it was a breeze until stage 31.
EDIT by Tom: Thanks Gambit. Sorry about the lack of warning.