Have you :-
-Resaved the config files?
-Checked Id clashes?
-Tried booting HDDriver, then Extendos/cddriver from not in the Auto folder?
I have current issue's with my cd/hd combination.
HD Driver misses my HD drive ? sometimes or waits about 20 atari seconds, then boots in 2!?
Currently running 4MB so some software doesn't like loosing memory.. off topic...