I have Flash as part of the Master Collection CS5 but haven't used it too often. Today I tried to import an 8 sec swf animation created from an AE composition (1920x1080PAL format) because I need to resize the swf down for a website. I resized it to around 500x310px but everytime I try to test or play this swf I get the revolving circle (egg timer equivalent) for several minutes before it finally crashes Flash. I tried to publish without testing but the result is the swf window is resized but the animation remains the original 1080 dimension - so only part of it is visible). Has anyone any ideas? Is it a programme malfunction or is it something related to my AE composition?
My guess is that Flash can't work with a file of that size. If you have the original After Effects file, you should try and create the .swf from that to the size that you need. If you don't have the original file, but just the output, you may be successful if you try to reduce the stage size in several steps. Try reducing the size by 50% at a time.
What format is the AE file that you are working with? Is it a video file?