Don't use the ground connection... instead rely on the common return through the track, or for testing off the layout connect the ground to an outside running rail(not a trigger rail) of the switch.
Remove the jumper and set it aside. Connect/touch the accessory voltage(set to about 12 volts for testing) lead to each of the three terminals(AUX IN, TRACK JUMPER, & AUX GND) one at a time in order. Your results should be, in order, 1)switch powered, no power to track 2)track powered, no power to switch 3)short circuit.
If you get these results, but in a different order, the reason may be that the switches were wired wrong internally. There have been reports of this with O-72 & other FasTrack switches. If this is the case, you will have to ignore the labeling and go with the terminal that provides power to the switch, no power to the track, for accessory powering, & re-label the terminals.