Pancenter wrote: When the "Undo" menu entry becomes inaccessible, beware.. .you will lose work.
This is not strictly true.
There are many operations on FCP X that cannot simply be undone with Ctrl+Z, so the undo button greys out even when autosave is working perfectly.
Working in the keyword editor is a good example of this. You cannot do Ctrl+Z within the editor (but, of course you can delete the keyword from there). Click the edit button and you'll see that undo is greyed out.
If you come out of the keyword editor and into (say) the browser, you can undo a keyword you just applied with Ctrl+Z.
If you're getting crashes, autosave problems and the like, there is more than likely some conflict on your system drive. Create a new user and try FCP X from there.
I did this, and FCP X worked perfectly on the new account. To be absolutely certain my MacPro's system was squeaky clean, I then did a clean reinstall and FCP X has worked reliably ever since.
I have over 3700 clips on one event at the moment - probably not advisable but it's a good test. FCP X is coping very well but sometimes slowly. (It helps to work without the waveforms displayed as these slow things down considerably).
Do you have FC Studio or an older version of FCP on the same drive as FCP X? This is known to cause problems and not advised by Apple.
Andy
Andy