Hi
Thank you so much for your speedy response.
I've found the Cached Projects folder with today's date. The instructions that you sent are great but they only provide instructions for a PC. The instruction is to zip the file BUT they display an instruction to "add to db.zip. On a MAC I onlly have an option to Compress the files.
Also there is no file called 'already in use.lock' and the file structure I can see is not like the the one displayed on the page.
I have compressed the file, changed the extension and tried to open a couple of times and each time it crashed again.
Any other ideas?