I use fcp and compressor ass well. When I download movies (which is legal in my country) and they are in divx I only could play them in VLC. But the solution to play them in any product of apple is to get quicktime to read it. And for that you need a component. You can gather them from the internet, or you can get them all at one through perian. Perian has placed the most in one package. So download perian from perian.org and install. (instructions on there, but the help you a little bit finding the library: go to finder, macintosch HD and there you'll find library). Good luck.