I found a good Actionscript / Flash Blog that has a good collection of handy tips and info.
Here is a link to a post that might be handy in the future about garbage collecting to free up memory and improve performance in flash.
This might have been helpful for my major project last school year which suffered a bit from slowing down. At the time I used .unloadAndStop() to shut down my loaders, which helped a bit but not as much as I would have like.
It also mentions a debugger that I had a quick play with: MonsterDebugger