Walked the robot around at the GenCon Stink for a while until one of the servos suddenly stopped working. Gears are intact. Seems to be a dead control board, although nothing is obviously burned out. Swapped the servo and the robot is walking again. Also one slightly cracked servo case and one loose servo horn screw, both easily fixed.
Radio range seems to be a lot shorter than at home. I blame the large number of cell phones. Must invest in higher power transmitter module after convention.