Nope, the LCRX and driving the relay from the light output, I use AUX2 to toggle the car on and off. I have a bulb showing through a hole under the car so I can see when I have the power to the board.
I don't really think the LCRX is all that suitable for the milk car, you want a fairly short timed pulse to eject the can and then go away. The ERR Mini Commander with the high current output is designed for this task, that's how I did my milkcar. The ERR solution also allows you to set the voltage and timing of the output so you can tune the ejection to the car.