10.0.9 Unable to Export Timeline

Question

I'm seeing a lot of discussion over this and have searched the forum. No definitive answer so I am reposting here.
Problem: If I try to export aka "share" my timeline FCPX will crash at some point. I have gotten then Error 1 message with an offending frame value but most of the time it just stalls and I get the spinning wheel. Shortly after this the computer will lock up (not kernel panic just all applications and Finder freeze - and cannot force quit) and I then have to manually restart the machine by holding down the power button.
I have had this issue on MULTIPLE projects using different media from MULTIPLE cameras, all of the Canon 5Dmk2/mk3 and 7D variety. The projects all use mulitcam clips created in the latest version of Plural Eyes 3.
I am running FCPX 10.0.9 under OS 10.8.5. All projects running off of firewire 800 drives. I have not updated to Mavericks yet as it appears this does not solve the problem. I have a MBP 3.06ghz intel core 2 duo with 8GB RAM and GPU enabled, not the neweset machine but works just fine for editing even without proxy media.
I am not using any proxy media.
I have deleted all render files.
I have trashed prefs.
I have repaired disk permission.
I have created a new user account.
I have reinstalled FCPX.
I have checked for updates - there are no updates besides the new OS, FCPX and QT ProApp Codecs are up to date.
I have copy/pasted my project into a new project.
I have duplicated my project and events to a fresh drive.
I have hidden unused projects and events.
I have tried exporting using different codecs ProRes 422, 422 HQ, H264 etc. they all fail though at different points it seems.
**The only thing I have noticed that works is that if I go to a DIFFERENT MACHINE - either my iMac at the office or my friends MBP it renders out without any problem...** I cannot figure out what would be different about my machine after doing all of the above!
So, I am able to create and edit on the timeline but render it out on this machine. It will also crash when I try to "render all" on the timeline. The video is only 5 minutes long and contains no type or motion effects. No third party plugins are being used on the timeline.
Any help is greatly appreciated. I have not done a witch hunt for bad frames as some suggest with ther error 1 message because I only have seen that message once and from what I am finding on the forums it doesn't seem to help much anyways and the issue seems to widespread. I am reluctant to update to Mavericks becuase I have not seen that it will solve the problem, just introduce "app nap" and possibly other issues.
Again I've tried about EVERYTHING as you can see and need to get this project off to the client, please if you have read the above and have any insight it would be massively appreciated.
Thanks,

Answer 1

When I asked about codecs I was thinking of conflicts that FCP might have with one that would have been installed from a third party vendor…
It would seem to be something at the system level since all the user-specific fixes appear to have had no effect. And you've already tried a comprehensive list of the suggestions that I would have thought of…and probably more.
You didn't mention available disk space but I assume you checked that as well and you have at least 15% free on your start-up and media drives.
Has any version of FCPX performed for you as expected in the past?
When you uninstalled the app, by any chance did you use FCS Remover? If you didn't, give it a try.
Russ