Yamaha DTXpress/DTXplorer/DTXtreme

Hi Guys!!!!

I have just aquired a dtxpress and love it to pieces. Only problem is 
that I can't seem to send/ recieve sysex files properly. When I use 
the dtxpressions program, it quickly says "sent!" on the computer 
screen, but nothing happens in the drum brain.
If anyone has some ideas I would greatly appreciate it. Thanks!!!