I work for a small production company that has a lot of outputs and requires a set of eyes to find any flash frames (green frames, black frames, or other). I'm working on FCPX and sometimes flash frames pass through the Quality Check undetected. We've used edit detector which works alright for green frames that FCPX 10.0.5 creates, but if there is a flash frame of another shot it sometimes can be missed (especially in the case when an old show export is used and extended just one frame too long).
The shows are around an hour and edited quickly, so if there is any software or procedure you could recommend that doesn't involve going through cut by cut that would be really appreciated.
Are you opening up an old version of FCP X with archived projects? Or is that the version you currently use?
10.0.6 and older was tricky with copy pasting into projects. Things would shift, this was fixed by 10.1.
If you do want to try and convert to the latest version make sure you do it using copies of your events and projects on a completely separate media managed drive and don't have the original drive hooked up.
It may not work perfectly but once you fix any translation issues you won't have to worry about outputs again. (I know, not the question you asked.)