You probably get the same result when choosing other machines in UAE because you are still booting it with KS1.3 instead of 2.x or 3.x. That would produce the same result. The ROM is the key here.

(that beeing said, I have no idea if it's possible to boot an A1200-config in UAE with a KS1.3 ROM image file....)

if you leave the disk in after it's loaded kick1.3 and reboots it just loads again failing on the assign this time because now your on kick1.3.