Q: Final cut pro 7 greyed out !! HELPP !!

Do you have FCP X installed already?

If so FCP 7 will not install.

Did you have FCP 7 on your computer previously and are reinstalling for some reason?

You did not remove all traces of it. It is much more than the software in your Applications folder -there are many files at system level.

Go here: http://www.digitalrebellion.com/fcsremover/ and use the tool to completely get rid of all traces of previous installations.

FCP X can be downloaded again at no extra cost but you must install FCP 7  first if you want both.

Also, a much simpler way which worked for me was just to rename my Final Cut Pro application file in my Applications folder from "Final Cut Pro" to anything else (I used "BLERP") and then my Final Cut Pro 7 install went fine!

I had the same issue. I had FCPX before 7. Just rename 'Final Cut Pro' in your Applixations folder to anything else and it will work! No need to uninstall X.