If you are doing a hdd install with the knx-hdinstall script then just say "no" later in the install process when it ask if you want to add lilo to the boot record and say "yes" when it ask you if you want to make a boot floppy disk.Put a blank floppy in your drive first and it will write a disk for you.

If you want to boot the cd from a floppy disk please see the "cheatcodes" and change the cdrom directory and the boot.img to your needs.

Also this may be of use to you http://btmgr.sourceforge.net/