I don't think it was a problem with the tweak; I've used it in the past and at this moment. Did you have the homescreen settings app? It might've been the color code you entered since the system does not take them all(but I don't think this is what caused it).

By the way, I think this thread should help with your flashing problem...
http://talk.maemo.org/showthread.php?t=87984