FCP 7 lost sequence after exporting - auto save vault not working

I started a project a couple of days ago. Today I worked from 11.00 - 20.00 hrs. I exported at 20.00 hrs. to compressor (i got a self contained compressed .MOV file out of that pffff)

But then, returning to FCP 7, the sequence I exported (and worked on all day) was completely empty. Everything in the project folder is still there, but the cuts / edits in the main sequence i worked on are all gone.

Inside the Auto Save Vault are only four saves from between 11.00 - 11.30 hrs. (not properly every 5 min.) and one from 20.00 hrs. The one from 20.00 hrs. is a version that also has the empty sequence. The whole afternoon FCP 7 seems to have made no auto saves, even though i set the Auto Save Vault to "every 5 min." in the preferences. Auto Save Vault files (of this same project) from a couple of days earlier are all there inside the Auto Save Vault folder.

Tried already: Looked inside the other two locations where i have autosave folders of other projects but the files were not there either.

Had a Tiff in the sequence, and a couple of very simple text-motion things.

Can anybody tell me whats going on?

And if there is a way to retrieve?

Never had this before, is this a FCP7 Yosemite issue?

Thanks in advance!