Hi,
I added
export BACKUP=0
to the last line of my .profile (which is at /home/tc) and did a backup and restarted. but when I click on the Exit button again, "Backup" is still at default. I thought that even if I clicked it, it wouldn't backup, but it still did, as it took several seconds before the screen vanished as opposed to immediately closing TC when I select None. I checked .profile and the line is still there so the original backup succeeded.