[RyanShoff]

The way I read the rules was this: if you can control something (ie break out pwm signals) and have active components, you needed to send it to FIRST a while ago.

I assume the reason is this: there could be a trace from the arduino to the pwm that could cause a motor is run outside of the safety systems.

I also read the rules to say that if you don't break out the pwm signals, you can do whatever you want. Lights, sensors, and coprocessors would all be allowed.

Not populating the pwm headers would be good enough in my eyes. I'm not sure every inspector would agree.