Lets try this scenario. We have a MIDI track with drum notes on it. We will use the synth rack to install a drum sample player. In my case it will most likely be BFD2. The Browser holds the synth rack. As you install this player a dialog will appear that allows one to set up how the player will work with Sonar. I most often want all synth outputs stereo. For a drum synth mono is a good option. When this is done click OK and Sonar will load the player and create a number of audio tracks that have as their input the audio out of the synth.
Next I simply route the MIDI track's output to the input of the drum player I also load the kit I want to be used.
After adjusting the MIDI also known as editing, when satisfied I freeze it after I have set the internal routing the way I want it. That is each sound going to its own audio track. Going back to the synth rack I hit freeze of that synth. Sonar starts creating audio in each track.
From there I can do anything I wish to the audio. But I can also unfreeze it and start over if I wish. With a freeze the the synth is bypassed and the MIDI is muted.