When using C6 software, if you press the CONFIG button before transferring data (and change Config settings or not) after this C6 will not transfer data. It just sits there. Tried it several times before I figured out …
…If you do not open the CONFIG menu before transferring data, C6 works fine.
Just thought I’d see if anyone was aware of this bug or not.
Mac OSX 10.7.5 (Intel Core i5)
I have not had this issue.
I changed the REC MODE in config menu multiple times.
I just had to be sure to hit ‘stop’ to kill any hanging sends/receives. Also, I did have glitches after I unlpugged the device, then plugged back in. Restarting C6 fixed this.
a bugg??? with c6??? impossible! 
Yesterday had an issue with C6: was trying to trasfer a pattern+kit from my computer (osx 10.8) to my Machinedrum with a DIGI002 as MIDI interface. Had no luck. So I switched to another MIDI interface, M-AUDIO FW410, and bingo! Strange enough since never had a problem with C6 and DIGI002 transferring to and from Monomachine. I find C6 to be buggy (still). Anyone had luck with some other sysex manager?