Here’s what happened: I created 9 text documents in the draft folder, named all but one and filled out the synopsis on all but 1. I had a text file that I’m using on this project, and I divided it up among the first four documents. Then I got up and made lunch, leaving Scrivener running. When I got back, I had lost the synopsis data on all of the items with empty documents.
Closing and opening did not create a repeat of the problem, and as I was away from my keyboard I can’t give any more details.
(I’m running Scrivener on Windows 7)