Good question, I have got a similar one, in that, when I import one of my combinator patches for a drum kit I have previoslly used, no sequencer track is created for the re-drum, only the combinator. Is there a way of creating one for the re-drum within the combinator. In reason 3 I would just right click and go to create-sequencer track for device.

At the moment I need to create a new one outside of the combinator so a sequencer track is created then move it into the combinator and copy the patch from my original re-drum.