There's a diecussion group on Yahoogroups:
DTXpress@yahoogroups.com
You will need to become a join up with Yahoogroups, and then become a member of the DTXpress group.
There's this helpful Web site which has a link to the discussion group from it, plus some useful 'tips & tricks':
http://www.thehearns.fsnet.co.uk/dtxpressions/ I've only just got a DTXpress kit myself, I really need the reference manunal for it, but there doesn't appear to be any way to email Yamaha UK to ask for one.
I've tried to contact Yamaha in Japan, but as of yet I've heard nothing back.
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