I suspect there are several issues here.
The first is the Unit= number in the PlayCD icon.
UNIT=0 is usually the boot drive. Do you boot from the CDRom or a hard drive?
If the latter, the PlayCD UNIT=number should coincide with the location of the CDRom you wish to use for PlayCD. You can't use both (if I understand the IDE setup correctly).
So, Unit=0 is the Channel1 Master (Boot disk)
Unit 1 is Channel 1 Slave, Unit 2 is Channel 2 Master and Unit 3 is Channel 2 Slave.
Also in the PlayCD icon, the DOSDev= setting should correspond with the icon you use for the selected CD drive DOSdriver icon. It could be CD0, Cd1, etc.
I have DEVICE=scsi.device in my PlayCD icon and BUFMEMTYPE is active.
Cheers,
JaX