Oha! You're right, that's not nice. Some (maybe all of them?) of the missing ones occur as combined MSB/LSB message, eg your wanted cc40, which is 'Balance LSB' message in the General MIDI protocol and as such handled together with cc8 (Balance MSB) by ReaControl. I didn't notice that yet. Though handling MSB/LSB in one slider is a good thing most of the time, we should of course request that the missing cc numbers are made accessable seperately as well, because a lot of synths use CCs in a non-standard way. (EDIT: Plus there are alot of synths making no use of the extended resolution at all, I'd rather send them my volume or expression messages in the good old 128 step resolution, seems to be much cleaner on the MIDI cable... (/EDIT) This could maybe be handled technically by using something like extended .reabank files to change the pulldown entries in the controller section of ReaControlMIDI. That way we could make tailored cc message pulldowns for synths, where eg cc40 could come up as "filter cutoff" in a virus.reabank file and unused cc's could be left out making the pulldown shorter. (I'd love to have that in the MIDI editor...) *Hint to Schwa*: afaik cakewalks instrument definition files (*.ins) which are partly supported by Reaper can contain such information. One workaround in the meantime is to insert another plug downstream of ReaControl which would change a cc message you can handle seperately (and you don't otherwise use for controling the virus) to the desired cc for your virus (I am not a tad jealous, no. :)). The most simple one I am aware of is JS: Chris/midi_cc2cc. It can only map a single cc though, so you would need an instance for every cc you want to replace. There may be other plugs which can map multiple cc in one instance. I agree this is not super convenient, but a way for you to send eg cc 40 to your virus from ReaControl right now.