Oxygen25-Xpand-MPC2000XL MIDI problems

[ALSABBADASUMMERSUN]

Peace. Here's my problem: I want to play the Xpand plug-in in Pro Tools 8 (mac) with my Oxygen25 midi controller (which only has a usb midi i/o) whilst the performance is recorded into the sequencer of the mpc2000xl (which is sync'd MBClock to the Digi002). So that I could if needed playback the sequence from the MPC with external midi hardware (ie a BassStation). I currently have the lab configured as follows:

Oxygen25...to usb port on Mac (active as a midi input device in PT 8)

Xpand on an "instrument" track in PT

MPC2000xl....MIDI ports A "handshaking" the midi IN and "1st" midi OUT on the Digi 002. The "2nd" midi IN on the MPC is connected to the midi OUT on the Digi002.

*I can trigger the Xpand plug-in from the MPC with the track type set to midi and the output for the track (on the MPC) to 1A-Device01, however if I set the output for the same track to say.. 1B-Device17 the Xpand is no longer being trigger/sounding.

Any help is welcomed.
Peace&Love