I've sent several bug reports. Even their official reporting system is a joke. They don't even respond saying "this is a problem but we're unable to fix it right now. The only reason fireworks is around is because it was first and now people are dependent on it.
This is indeed a total joke ! It worked fine on my last Mac Pro which was upgraded to Mountain Lion but I get the bug on my new Mac Pro which had Mountain Lion installed before I installed Fireworks !