Ok, it seems your OS and FCP7 are conflicting because FCP7 can’t choose one of two identical files.
I checked my Lybrary to see the duplicates you have, and all i got are alias. I dunno if it’s safe to trash those, but if you already have a conflit, why not? 🙂
Before that, have you connected to App Store and done the latest updates, after you installed FCP7? If not, it might be lacking an update of the ProApps