Just had a weird thing start happening with a particular project. Running Flash 8 on a dual 1.8 G5, OS X 10.4.3.
When I'm publishing my file (or running Test Movie), Flash seems to hang in the process. I say "seems to" because according to my Activity Monitor, it's running fine, although processor use does fluctuate between 75 and 99%.
It does create a .swf file of about 4kb, and the progress bar stops at about 20-25%. Then it sits there, doing nothing...much like I do, staring at the screen, wondering why few things in life are truly "easy". Anyway, I get bored watching nothing happen, so I click "Stop" to stop the export, but it doesn't work. I have to force quit the app.
This doesn't happen on any other project; all other projects export just fine. This fact alone, frankly, frightens me.
I've had a similar thing happen on a somewhat large and complicated project where I worked on both Mac and PC during developement. It would take about 30 minutes to export on the PC, but if I tried to export on the Mac it seemed to hang, "SEEMED TO" being the operative word. It didn't hang, but actually took over 3 hours to export. The Mac was a new Dual 2.0 G5, which certainly SHOULD be faster than my 1.4 P4 PC Laptop. I'd set it to export overnight and see what happens by morning.
I've been having a similar problem as well. I have built an interactive with a huge number of layers. When I publish it hangs. When I reduce the number of layers (and therefore the number of symbol instances) it publishes fine.
According to http://www.flashmagazine.com/437.htm one of Flash's limitation is related to the number 160000.
Your problem can be related to the number of layers, vars or symbol instances exceeding 160000. The article doesn't mention anything about it hanging when publishing but like I said when I reduced the number of instances it published fine.