I have without any problem used knx-hdinstall (0.3 to install clusterknoppix (vers 3.2.2003-05-20)to a hdd from a cd.
As it is a 20gb hdd I had already created multiple partitions in a previous Debian install. Cfdisk showed them as available and in the create file system the script asks which one to use for a root partition. (I believe I could have created the same number of partitions in cfdisk as part of the install if they were not pre existing)
The problem is the install only copies all the files to that single partition and at no time did I have the opportunity to elect to use any of the others for /usr /var /tmp etc .
The fact that a second hdd was also available never arose.
I believe it is possible to move filesystems to new partitions as a standard Linux administrative task, and then mount them in fstab at boot up however my efforts to do this have ended up in a mess to the point that a reinstall was quicker and easier.
So far I have not found any relevant documentation to help and my understanding of the script is not good. Some documentation on this site comes close ie creating another /home but I am looking at using about 12 partitions.
Any assistance would be appreciated.