I’m talking about the generic generic remote XML.
About the NRPNs, it’s generated by the OSC-to-Midi bridge I wrote to work with TouchOSC (or any other OSC client).
I don’t do anything with inc/dec messages.
Check the MPK manual if you can set the rotaries to receive the “transmit” data from Cubase and send updated data.
Or if you can have them send “1” for counter-clockwise and “127” for clockwise and set in Cubase to have the control set to Relative.