FCE file suddenly won't open; FCE crashes

Question

A FCE 3.5.1 project that I've been working on for months, suddenly crashes the application.
The file is 3.5Mb. It opens to 48%, says it's "preparing video for display", and then "FCE quit unexpectedly". Other projects open fine. I've removed preferences and reinstalled the application from scratch - no luck. The last time I opened and edited the project (4/6/08) it worked fine; quit gracefully. Since then, I've done a few SW upgrades (listed below). Using Time Machine, I went back to the previous version of Quicktime - no luck. I added another 1Gig of memory - no luck.
I'm starting to panic based on the hours I've put into this project to-date.
2008-04-06 21:59:17 -0700: Installed "Keynote Update" (4.0.3)
2008-04-06 21:59:25 -0700: Installed "Front Row Update" (2.1.3)
2008-04-06 22:00:02 -0700: Installed "QuickTime" (7.4.5)
2008-04-06 22:01:01 -0700: Installed "iTunes" (7.6.2)
2008-04-09 19:53:37 -0700: Installed "Aluminum Keyboard Firmware Update" (1.0)
2008-04-09 19:53:42 -0700: Installed "iMac EFI Firmware Update" (1.3)
2008-04-13 08:53:03 -0700: Installed "Final Cut Express HD Update" (3.5.1)

Answer 1

Additional information: I get the following messages in Console when I tried to open the project in question.
4/14/08 8:15:29 PM [0x0-0x18018].com.apple.FinalCutExpress[171] Final Cut Express HD(171,0xa02bffa0) malloc: * error for object 0x2bdba600: incorrect checksum for freed object - object was probably modified after being freed.
4/14/08 8:15:29 PM [0x0-0x18018].com.apple.FinalCutExpress[171] * set a breakpoint in mallocerrorbreak to debug
I deleted the render files and the error in Console changed to the following:
4/14/08 8:15:33 PM com.apple.launchd[105] ([0x0-0x18018].com.apple.FinalCutExpress[171]) Exited abnormally: Segmentation fault
4/14/08 8:18:03 PM Finder[119] NSOpenGLAutoscaleBounds=NO
4/14/08 8:19:05 PM com.apple.launchd[105] (0x10ae10.Locum[183]) Exited: Terminated
4/14/08 8:20:14 PM com.apple.launchd[105] ([0x0-0x1e01e].com.apple.FinalCutExpress[184]) Exited abnormally: Segmentation fault
Thanks for any help received.