What? I can run FCP X 10.1 and 10.0.9 on the same Mac?

So I made a fun discovery today on accident and felt like sharing it. Would you like both FCP X 10.1 and 10.0.9? Normally no, I would say, but backwards compatibility can be a valuable thing. It is possible, here's the link to an article I wrote up on how to do it:

What? I can run FCP X 10.1 and 10.0.9 on the same Mac?

Hi,

On top of your discovery I found out something else.
Although my upgrade to 10.1 went flawless, I forgot to make a zip archive of my previous version 10.0.9.
So I went into Time machine and opened the Applications folder from the day before the 10.1 update.
I opened the Final Cut Pro folder and right clicked on the Final Cut Pro app.
I selected 'Restore "Final Cut Pro.app" to...' and Time machine brought me back to today. Then a finder window opened so I could specify the location for the restored file. I made a new folder and called it "FCPX 10.0.9" and clicked "Choose".
When the file was copied I right clicked to zip it into an archive.
Then I wondered wether to throw the original 10.0.9 file away or if I might try to open that app, instead of 10.1. I chose the latter and guess what, I had 10.0.9 running! Closed it and opened 10.1, no problems, apart from having to change some settings for the browser again, like Events on second display and set the "Group Clips by" to none again.
I did no extensive testing with this, so you it will be on your own risk if there is any.

Cheers,
Robbert-Jan

I mentioned this in another thread but if you keep one of the versions in it's own folder in the apps folder and make a different user this should work fine. FCP X uses the same preference file names in your user library so it's overwriting 10.1 and 10.0.9 respectively every time you switch. If you make a 10.0.9 only user account this won't happen.

To be on the safe side, use event manager x to hide the 10.0.9 events/projects you want to keep unchanged.

Thanks for the tip Darren.