C6 was / has been working fine for me up until about an hour ago. I now have the same problem, when I click on config it quits (Mac 10.9.2 & C6 1.5)
So now I can’t transfer any samples to the RYTM… No idea why it’s stopped. I went for dinner and now this weirdness.
I really wish you could just copy (and manage) files to the RYTM via a USB mounted drive. Would be so much simpler and user friendly.