Yamaha DTXpress/DTXplorer/DTXtreme

Hi gang,
  I'm new here, forgive me if this question is old hat.
  I just tried to hook up my DTXPOLRER via midi-out to my PC and I
don't seem to get the snare or bass drum.
  Yes, I got the infamous midisport Uno midi/USB adaptor.  I'm using
nuendo with the VST sound plug in "Plug Sound Pro by Ultimate Sound
Bank".  The Plug Sound Pro VST has a few dozen drum sets but they all
seem to not play the bass drum or snare (the hi hat, cymbals and toms
are coming out).
  Please help me, oh wise ones!
Thank you 
Kurt M
frustrated in Venice Ca.