I have a 2009 unibody mbp, 4gb ram, 500gb 7200rpm HD..... I'm running FCP 7 with the project running off of a western digital external. EVERYTHING is so slow and messed up, it's unusable basically. I'm working with XD CAM HD footage btw... Also there is only 5gb left on the external drive I am running/editing the project/clips off of, and only 40gb left on my internal drive. Could this be the reason for it running so ridiculously slow and laggy? Or something else?