I don't currently have any MIDI devices, so can't really make this or test it for you. Its not massively high on my list to do atm either
But as SpoonMan says, the commands would be exactly the commands that the web interface sends when you use something like the web interface scene color changer. Given an example bit of code that gets the value for each channel from a Midi instrument its dead easy to do the rest
If its in Java I can provide you with the code to send different values to R4.
Actually, I'll do some code tonight that controls the options in R4 from some Java Scrollbars. If I don't do it, keep bugging me.
Sorry - just been very lacking in free time/motivation lately