Running acessories on Atlas track

  I use two 6015   1.1/4" straights with insulated rail joiners on one outside rail.

Attach a wire from  each insulated rail and power from the transformer to the Highway flasher and your done. easy peasy nice and easy

As for the x-ing flasher, if you use the modern version, you can rund it off the insulated rail.  Lionel and MTH versions have the circuit board to alternately operate the lights on and off.  Simple to wire hook up.  You can do the same for the signals but if you use the more modern versions verses the post war ones, I would run them off the 14v acc'y tap and connect the ground wire to the track.  They will lite up for you either red or green....

Marty

There are also IR sensors to install along side of the track to trigger accessories, the Lionel 153IR comes to mind as a good choice.

You can make outside insulated rails with Atlas. They sell plastic joiners for that purpose. I use insulated rails and relays. . 

LINK

Dale H