Unzip/unrar the Bios files (dc_bios.bin, dc_flash.bin) on the same folder than Chankast. Then select the drive (Options -> Configure Drive) you're going to use, etiher real or virtual like a Daemon Tools one. Now config the keys as you prefer (Options -> Configure Controls).
You need some ISO/burn CDs tu run in the emu, as originals wonit work because the incompatibility of the GD-ROM format.