kl522, I followed your criticism and I moved the same working configuration from the internal HDD to the USB drive to the NTFS partition (the former was ext2) and I can boot KNOPPIX finally.

If I add the cheatcode desktop=kde I get the following error: "Call to lnusertemp failed (temporary directories full ?) Check your installation"

can you suggest a working set of cheatcodes for kde ? gnome and lxde work fine.

thanks again
benny