Hi,
Ok, I've found it. there is CD-Rom support build in into Workbench 3.1.
There is an according entry named "CD0" in the directory "Storage".
But you have to adapt this file to your system. You have to know the name of the device your CD-Rom is attached to (e.g. scsi.device) and the unit number of the drive.
If you own the full documentation to Kick/WB 3.1, take the Workbench manual and have a look in chapter 4.3.5.3.
Noster