"Revive" Old version Final cut pro events and projects

Hello,

A few months ago I copied my Final cut pro app from my Mac Hard Drive to an external one. I have been working on a few projects (on the hard drive) for a while now. However, recently the most awful thing happened. I updated my system to Yosemite. I found out that the new version is not compatible with the old version of Final Cut that I've been working with (10.0.0). Inevitably, I had to update my Final cut pro (risking loosing those projects etc.). Since, the Final cut on the external hard drive was just a copy, when I updated Final Cut it updated the original app on my Mac hard drive. Hence, I tried copying this new version into my external hard drive (along side the old version), crossing my fingers that somehow this will work. Of course, NO LUCK. When I opened the new updated version of Final Cut from my Ex. hard drive. The old events and projects (which are saved under "Final Cut Events" & "Final Cut Projects" in the same folder as the app on the Ex. hard drive) were missing. I now wonder, is there a way to "Load" the old events/projects from those folders? Or some other solution? Those files appear as text files and not Final Cut "related" files (with a Final Cut mark or so). For Eg. "CurrentVersion.fcpevent" = text file.

I have another mac computer that I haven't updated to Yosemite yet! However, When I try to "double click" the file ("CurrentVersion.fcpproject") it tries to load it forever, but at the end- gets stuck and does n-o-t-h-i-n-g!

I am desperate for a solution! Among the projects is a Music Video I have been working on for a client for a very long time now...😢

I would appreciate any piece of advice.

Thanks in advance,

Tom.