Hey,
I've had a look through the project and it looks like the last time it was saved it was interrupted before it finished. Event sheet 2's file went missing, and some other events looked like they'd been corrupted.
I'm not sure what happened. Can you remember what were you doing before the last time you pressed save? Were there any other error messages? If you used save-as, renamed any event sheets, or did anything in the project - there might be a bug in the software for one of those things.
It might happen again since C2 is beta software, so I hope you remember to keep backups! Just in case, I've managed to restore what looks like most of the project - you can download it here. Event sheet 2 went completely missing I'm afraid though, so is empty.
(Just a heads up, the project is already over 25mb in images alone - that's a couple of minutes download time for most people!)