Yep, the "ROLLER" lead has to have positive going power, for the lighting outputs in command mode, that would be ground. Note that anything on the output of the power supply MUST be isolated from chassis ground.
You do not want to interrupt the headlight input on pin-3 of the Super-Chuffer, that comes directly from the TMCC package. You just tap into that to also power the supply for the MARS light. In addition, you don't need the 22uh choke if you power it from the headlight output and not track power.
