I finally managed it the other day. I’m not sure what I was doing wrong, though I suspect that the fact that I didn’t have much webspace wasn’t helping, when trying to extract files etc.
After a lot of attempting to delete whole directories in WS-FTP lite (is there a way to get it to empty folders that have contents. If there is, I never found it), and attempting to restore to the earlier version, all of a sudden it worked.
All seems fine.