Channel Aftertouch lost for Drum Maps

In Superior Drummer, Channel Aftertouch is used to mute crash cymbals. When using a drum map, the Channel Aftertouch is missing from time to time (at least, the cymbals don't mute). Without a drum map, this doesn't happen, so I think the problem is due to drum maps in Sonar.
 
This is reproducable in projects with nothing but Superior Drummer and with a drum map only for the crash cymbals. However, larger drum maps seem to cause the problem more often.
 
Sure, there's a simple workaround by moving the Channel Aftertouch events into a separate track without drum map. But this means additional work and corrupts the workflow.