[DonaldM]

Create an audio track for the drums. Then route the output of the instrument you're using for Reason and Redrum to the input on the audio track (just use one of the empty busses you have). Record arm the audio track, and when you play Redrum, you should see the level meter on the audio track responding. You may need to adjust output from the Redrum instrument track to get the input to the audio track where you want it. Hit record and you should see the audio track print.

Hope that helps.