FCPX corruption extends to backups

Editing concert footage, solo violin, I experimented with a pitch correction filter and the application unexpectedly shut down. When I reopened it, all of the the opening titles were scrambled: old fonts were double exposed on top of new ones (see picture), some were missing altogether, and others showed up in the inspector though did not appear in the timeline.

The corruption extended to all of the backup versions since this morning, when I introduced the titles prior to working on pitch correction.

STEPS TAKEN (please read before you advise me to trash prefs, thanks)

1. I restarted the computer
2. I deleted FCPX preferences (Quit Final Cut Pro; Hold down the Command and Option keys, then open Final Cut Pro; Click Delete Preferences.
3. I restarted the computer
4. I deleted the application
5. I reinstalled the application
6. I deleted generated library files for all projects, including the backup projects that I had opened.
7. I deleted the com.apple.FinalCut file in user—>library—>caches
8. I restarted the computer

Nothing has worked. Any idea what went wrong or how to fix? Very many thanks!

FCP Version 10.7