Clone save sets from LTO1 to LTO6

A friend of mine wants me to copy 4 x LTO1 Networker tapes to a single LTO6 tape (he doesn't have an LTO6 drive).

I'm a NW newbie so I've downloaded and installed a trial copy of NW (version 7.5), installed 4 x LTO1 and 1 LTO6 drives and I've indexed his tapes using the scanner command. I've labeled the LTO6 tape using the GUI (assigning it to the "default clone" pool), mounted the 4 source and 1 target tapes, and have tried cloning all his 2 dozen save sets by going to Media/Savesets in the GUI, selecting them, right-clicking, selecting "clone" and choosing the "default clone" pool. But nothing happens. No complaints, no request to mount any volumes, etc, nothing.

Elsewhere I've seen people remark that the GUI is a bit flaky and it's best to use the command line. Is there a straightforward way to copy the savesets from the LTO1 tapes onto the LTO6? Preferably reading from more than one drive at a time?

The goal is for him to have a backup of all his LTO1 data on an LTO6.