Problem solved. It was a configuration mistake in the location plugin! Storage Node info missing.

For the extra clarity, this worked for me. Edited /var/www/fog/lib/fog/BootMenu.class.php, the rows just below "…$option == ‘fog.quickimage’)

//              print "login\n";
				print "set username username\n";
				print "set password password\n";

/Thanks!