I've replaced the servo with the same results. It's pretty clearly a dead PWM header on the board. I can't track down whether it's hardware dead or firmware dead, as I don't have anything set up to reflash the bootloader. Would I just swap the 15 and 13 in the pwm_pin array? Do I have to remap it everywhere in the instincts and movements? Or is there one place where I can just change the output that's associated with the left-front elbow that's not working for me?