Thanks to you all for your valuable help. I accept that I should be doing a regular backup anyway, but consider my wrists slapped!!
I did a search and thank you guys, I fortunately found another Blackberry Backup folder (called Blackberry Backups!), in which resided a LoaderBackup dated the time that I did the upgrade!
Interestingly the application didn't find this folder to do the restore process from....whatever, I am completely back up and running and will be doing regular backups.
Now......what's this about OS6 ????