As powerful as the Flash technology is, this is about the worst program I have ever used on the Mac. There are HUGE bugs that Macromedia has ignored ever since MX was released. Copying and pasting several frames can send your machine into the spinning beach ball of death...even on 1 GHz+ machines with maxed out RAM. Switching to other apps while Flash MX is thinking will cause all your palettes/windows to disappear and force you to reload them...the work area window frequently loses "focus" so that if you try to select it, it remains inactive and in the background. Flash MX feels like an early beta. It's a terrible shame that Macromedia chose to release this software as is...very shoddy. Even worse, they have had more than a year to release updates to address these problems, but have ignored their Mac user base. Please, everyone suffering similar problems, please write to Macromedia and tell them to fix things.
http://www.macromedia.com/support/email/complimentary/main.cgi