problems with final cut pro x 10.2

4GB is not enough for a good experience with video editing, and updating to 8GB, if possible, may make total sense; but before you throw money at the problem, let's start with the basics: which version of FCP X and OS X are you using, and what exact model of MBP is this (if you don't know, hold down option key, go to the Apple menu and choose System Information... and post a screenshot of the Hardware Overview area)

The first course of action would be to clear the application's preferences, but again how to do this depends a bit on which version it is.

Luis' advice to clear the preferences is good advice. It may not be the original cause of your freezes, but anytime that happens there is a good chance that the application's prefs are going to be corrupted.

Increasing RAM s also a good measure, but lower-than-ideal RAM is not causing your problem…unless, of course, the installed RAM is defective. Run Apple Hardware Test (Apple Diagnostics). and see if it reports any issues.

Russ

In your version, it's done by holding down the option and command keys when you launch the application.

When it opens, you will need to navigate to your library from the File menu.

Russ

I couldn't connect to the support docs on this, so in the meantime…

http://macs.about.com/od/Troubleshooting/fl/Using-Apple-Diagnostics-to-Troublesh oot-Your-Macs-Hardware.htm