Thanks for the help. Where I am now with it is basically "half the way" there. Trying it out with 4 tracks only routed to the top 4 slots, I used the plugin that allows you to transpose MIDI notes coming from any given track. So in my case I've got that plugin on each of the 4 tracks, each transposing 2 of the Axiom's drum pads to each of the 4 slots respective REC & PLAY buttons. One complication however is that I had to set up the transposition values and low/high filter for each so that each cc number pair was unique so that there wouldn't be any unwanted "double triggering" action going on. BUT, currently, using the Reaper plugin that shows you all the MIDI messages that occur when any given MIDI message is sent, I'm seeing that in addition to the message that I do want sent, there is still some erroneous messages being sent as well. [Interpreting all this new stuff as I write...] What's happening is that the filters look like they're not working: although I want Ch. 10/cc42 to be received as Ch.1/cc 77 on Slot 4 only, what I'm getting is in addition to the correct, desired Ch. 1/cc 77 on Slot 4, I'm also getting an untransposed Ch. 10/cc 42 being received by Super8, and also these 2 other unwanted messages: Ch. 1/cc 7 being received by Super8 and by Slot 1 too. So say, when I want to record to Slot 4, some malfunctioning action is also happening on Slot 1. Any ideas how to fix this?