i went ahead and reset all the factory settings for the MXC, since I don't think I'm using anything strange. That worked, I was able to recognize the soft switch on the CC pedal via the MXC. However...the wah would activate in my GX-700 before the switch was clicked...the wah was turning on/off as soon as I had the pedal pushed all the way forward...very sensitive....too sensitive.
So, I thought I'd try the wah in the MP-2. The pedal seems to have zero effect on the wah in my MP-2. When I set the wah to 'on', it's on, but it does not switch on/off with the soft switch. When I change the midi assignment for the wah, it changes the frequency of the wah, but again, the pedal has no affect on the wah itself. Not to worry, I don't appreciate the wah in the MP-2 (I do like the auto wah though).
So, for now, I use one of the buttons on the Quad switch to turn the wah on/off, and the pedal to control it. That's working for me.