The PC0-file can be found either in
Devs/Dosdrivser or in storage/dosdrivers of your
Workbench-partition (DH0).
It must end up in devs/dosdrivers to be automaticly used
on boot-up.
@that_punk_guy
To bve honest I never used atapi.device, but unit 1 for the
slave sounds like the most logic option, as it allways could be
that someones has only a CD but no HD connected to the IDE-port.