I'm testing a little code snippit in CS4 flash (I know - upgrade already - I have but this one has to be done in CS4)
It doesn't get much simpler - object on stage and little code in the timeline that access that object.
All works great with preview as long as I haven't actually saved the FLA and everything is untitled. Once I save the FLA neither preview or running just the SWF works. It does fire up but non of the code runs - not even a trace in line 1!
I noticed a post about flip4 mac causing some oddities with flv's and the preference pane for flip4mac is fairly new in the system but I have removed that and still no joy.
Have trashed flash's preferences and zapped the PRam. Have even uploaded the created SWF to a server to see it run in a remote browser and get it away from my system - nothing.