No, I never tried Debian Remastersys and I can not say, if it will do the job. But you told us, you have experience with Ubuntu Remastersys; therefore you will be able to solve all troubles which may occur with Debian Remastersys.

With my scripts you need

1. a Knoppix HD Installation (you allready have)
2. a decompresses filesystem image at '/opt/knx/remaster' (will be done by the scripts)
3. all the bootloader stuff at '/opt/knx/' (will be done by the scripts)
4. repeat installation and purge of all programs and tools within the chroot jail, as you did within your HD Installation (it's your job)
5. build the new ISO (will be done by the scripts)