This is great to see, people showing how RO can be used as part of a music studio; I myself have always used my Acorns, in the past to make music with tracker software.
Now I'm running my own studio with a RiscStation R7500+, with MelIDI as my main MIDI sequencer.
The studio comprizes MIDI samplers & synths/modules, all programmed using RISC OS. MelIDI allows me to sequence it all with a good level of control. I'm working on my album (very slowly, as recently finishing at Uni' took most of my time) which is predominantly progressive/tech house & breakbeats (think Underworld, Orbital, BT et al) and sequenced completely with MelIDI, with some sample-editing done on ProSound.
When I finally release something, perhaps I could do a similar feature, about how I've used the platform in the studio environment.