I can’t give you a concrete answer as I don’t have a Linnstrument, but I can say that within the firmware all of the parameters you would be able to control with the Linnstrument are already exposed. If Roger setup the Linnstrument to use the standard CCs on much of the Linnstrument midi data, then I suspect you’d be able to plug a Linnstrument in now, and already get most of the MPE functionality out of it.
As of right now the midi module attempts to see what midi CCs are for pitch, velocity, gate, aftertouch, CC74, etc. Should be pretty easy to directly support the Linnstrument.
Bert or Celine will need to comment for the official stance however.