Yes, I used the tohd grub boot option at first like you described, that's when I got the kernel not found on <device> error. Same thing with the fromhd just in case you typo'd. Then tried it from a shell prompt just in case again. Nothing worked.

The install to hard drive (0wn script) lets me select the partition to install to, and select sdb (default) to install grub to, then I get an error saying "there was an error" "the system may not be bootable", which of course it isn't, then the 0wn script fails.

I might be able repartition and reinstall everything, installing Knoppix first, so it will actually install grub new, but I am not about to waste my time doing that.

My suggestion is for Knoppix to use the Ubuntu installer. It sees the USB as another HD in which you can install to any partition and install grub to sda/b/c/etc, or the partition you installed to, and never skips a beat.