In this post when I speak of the "Rear" I mean the part of the car farthest from the front of the motor home.. 
Many states have laws about the color of lights.. RED to the rear, White or Amber (Yellow) to the front.  So do not activate the car's factory lights. Use magnetic or other "Removable" Tow lights on it. (or the dolly may be lit but I"d still put lights on the hood of the car) 
Beyond that.. I do not think you should have any issues. 
Of course there are cops and there are cops..   I worked with some of the best in the country (Michigan state police, I was a dispatcher) but it was my displeasure to encounter a few who were not quite so sharp....
Like the one who gave me a ticket for disregarding a no turn on red sign..... that did not exist.