Yeah, that's the gist of it and the DM10 allows 35 extra instrument sounds to be triggered via midi, as explained in this topic: http://www.alesisdrummer.com/index.php?topic=92.0
Got it. Well, I ordered a set of cables yesterday which will arrive next week but I'm now contemplating how to use the Crimson unit. Last week, I set the kit up so that I had the Crimson module as the main module, with my two Yamaha PCY60 pads connected to the two additional triggers for splash and sizzle cymbal duties. I then hooked up the five Yamaha TP60's to the DTXpress module and configured them as percussion triggers (Hi Conga, Lo Conga, Cowbell, Claps and second Snare). What I might do now is retire the DTXpress to a back up role and use the Crimson for those extra percussive duties. Although what I may do is simply use it as a trigger connector and patch the MIDI through to the DM10 and use the sounds in there.
Exciting times ahead