I experienced the same and yes, rebooting seems to fix the problem. I've noticed, however, that even after configured (installing then rebooting) that if the MCV stick is removed from the USB to program another light and then plugged back in to the computer it still says failed to start.
Basically, I've found that whenever I do anything to the MCV z-wave stick that requires removal from the usb slot, I need to reboot the core with the MCV stick in the usb slot. Adding the stick after a reboot yields the same "failed to start message".