Program crashes when opening a file

[Joakim]

I've been working for several weeks on a single picture project and as I'm nearing completion the file somehow becomes corrupt and won't open in Pixelmator. My guess is that there are too many layers for the program to handle, as this has happened to me before with large files. Is there a way to fix this, perhaps an autosaved earlier version of the file or something. Not sure what to do here...