E-mail address assigned to this account requires confirmation. Check your e-mail for further instructions.
Follow the link in the e-mail, to start password recovery procedure.
Motion and Final Cut Pro tend to stack corrupted data in their preference files which often results in an unexpected app behavior (instability, crashes, artifacts, extended render times, etc) – because of that, Apple's support (and therefore we) suggest wiping your preferences once in a while.
To do that, launch the app with Cmd+Option(Alt) keys pressed and click "Delete Preferences".
Please note that FCP will not load your libraries by default, so be sure to open them via the File > Open Library > Other > Locate menu (they're the files with the .FCPBUNDLE extension which can be found in your Mac > Users > YourUsername > Movies folder).