I recently tried installing FCP7, but failed because the disc was damaged (i tried cleaning, like suggested in other threads, but it has a couple of scratches)
I now can't open Final Cut 6 any more, because some of my content files and plug ins etc were modified in my attempt to install 7.

So now I can't use either. Is there a way i can undo the damage i did by installing 7 with out deleting any of 6?