Hi, all!
I made my improvisation the other day and I hope it helps other people too.
I have the Line6 FBV MK2 (yes, the one without midi ports). I use the Bome Midi Translatosr (just a software) to send midi commands from the FBV, through the computer, to the sound card midi out which, finally controls the KPA. The sound card is a focusrite which functions as a midi breakout box.
So, it is the FBV >> computer (midi translation software) >> sound card >> KPA
It works like a charm, no latency. It was not intended, just discovered that it works this way when I installed the sound card and decided to experiment a little. You may use any usb/midi cheap interface instead of the sound card. It controls performances, rigs, effects, pedal parametres... you name it.
My guess is that the software can translate regular midi messages into NRPN messages, but I have yet to take the time and program it.
Have a nice day,
Catalin