Alt-F is a hybrid mutant, kind of Resident Evil (but without Milla); it relies on "settings" saved on flash memory, and on disk, so to start Alt-F as if it were the first time it runs on your box you have to "clear settings" and remove Alt-F traces from disk before rebooting or reflashing.
-Remove the Alt-F instalation from disk first, Packages->Alt-F -- that can be difficult or impossible, as it is probably being used. So the best is to deactivate it from boot and reboot; after the reboot you can remove/delete/rename the installation. Deactivation means creating a file named 'NOAUFS' in the Alt-F folder and rebooting.
-After that succeeds, remove or rename the Users folder to something else
-After that remove or rename the Public folder to something else
-Then "Clear Setting" and reboot
Alt-F will then run the first login wizard