As far as I know, there are no system requirements. Just download Make CD from the Make CD site, add to your HD, attach a CD Writer and off you go.
I am currently using a desktop and towered A1200 with OS 3.9 and the program works with my external CD Writer on my desktop and internal CD Writer with my tower.
The only problem is making sure your CD Writer is compatible with the Make CD program, but their site does a quite extensive list of compatible writers.
If all else fails, I do have an external Yamaha 6x4x16 CD Writer which is for sale as a spare and which I know works with Make CD, although you will need a Squirrel PCMCIA-SCSI interface cable to connect it.
Regards,
Mike.