I have recently bought a Hexy and already assembled it. However, servo ports 0 to 7 are not working. I.e. they neither center the servos nor do they react on anything I do in ProMoCo. The same servos on other ports are working well. I have tried different servos, one at a time, which proved working on other ports.
In my opinion, it looks like one of the 595 registers is broken.
Email firstname.lastname@example.org and we can get you a replacement board.