Looking on the first one (users.sisna) I found under:-
GENERAL PROGRAM ISSUES
"Issue: Family file: Rebuilding the index takes time -- especially with large files. Solution: Generations only rebuilds the index if the application doesn't close properly.If you don't want to wait for this, hold down the shift key while opening a file to avoid building an index."
Tried this but no joy. Then I tried holding down the CTRL key and then clicking on the uds file to open it and it WORKED.
After checking the TRASH bin and deleting what was in there (thought this might be the problem as I had been deleting a duplicate name)and then closed the file down and all works OK now.