Tony, there's a fairly complete description at Roland-arranger.com on how to use external modules with the G70.

In essence, it boils down to, for SMF and Style use, no problem, most codes can be written into the style or SMF, and a Linked MIDI set routes each Part appropriately. For live Keyboard Parts, it's a bit more complicated, but short story... You Link an SMF to the UPG that calls up the external Tones for you to play.

Full details here: http://www.roland-arranger.com/smf/index.php?topic=618.msg3498#msg3498

[This message has been edited by Diki (edited 02-26-2008).]