Yamaha DTXpress/DTXplorer/DTXtreme

I searched the archive for anything on recording and MIDI (still a 
bit confused). I have DTXpress II and plan on buying a 16-track HD-
recorder (fully MIDI compatible). I've understood that there is no 
clear answer to how to record DTXpress sounds on separate tracks. 

If I send MIDI information from my DTXpress to a multitracker, which 
track does the information exactly go to? Can I assign a separate 
track on my multitracker for each MIDI note number? And if only the 
note number, velocity etc. data is transmitted, how will my 
multitracker be able to play the right SOUNDS in the mixdown phase?

I could record via the line out each sound at a time (turning down 
the volume on all the others) but how on earth am I going to get them 
to play in sync?! 

Anyone who knows about multitrackers, please help!

-Antti