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If you are having issues, you should describe them. Otherwise it just sounds like you are asking out of curiosity.

No, I haven't heard of such problems, but then I don't follow the latest FCP issues.
 
Not too many problems. What are you experiencing? Is this with a new project or using an older one?

Otherwise try repairing disks permissions. Then do any updates. Power-cycle the Mac and try again...
 
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