the shield is not using the serial pins. It plugs into 5 volts (l293d only), ground, and pins 6,9,10,11. On the shields with the error problem the error occurs when the shield is plugged in to the arduino and without the secondary power hooked up. Holding down reset at the start of the upload does not seem to do anything, but i will test that on some of the other boards during the class today.