Please check if the HDD is jumpered correctly (master).
Try to jumper the HDD as slave and the CD-RW as master.
Try to boot from floppy disk with only the CD-RW connected (first as master, and if it does not work, as slave).
If you've got some spare money you could buy a buffered 4way-adapter, connect the HDD to its first channel and the CD-RW to its second channel, both jumpered as master. Now you *need* IDEfix software for the CD-RW, but it might work.
If you've got even more spare money, you could buy a FastATA4000 controller to run the CD-RW. ;-)
Bye,
Thomas