is it this one?
http://www.powerdrumkit.com/support.htm
I downloaded this one and tried it. Was a cinch
insert>virtual instrument on new track
then select yes for multi out or no for stereo (multi out allows for mixing in reaper)
if you do multi out just go to the MT Mixer GUI and set which output for each drum piece and signal will show up in reaper on those seperate tracks.
I've never used reasamplomatic but on this kit i dont think you would need to for basic use.