I believe since your MKX has no ignition key, that you will require a charge line to your car. From my experiences, two hours or less in accessory position drained the car battery. Once I turned the key off..no more problems. With the push button, you will have the battery drain problem unless you do. As far as neutral tow, is concerned with the cvt transmission, absolutely no problem and I 'exercised' the gears every four hours or so anyway. No smoke and no funny noises when driving the car 2,500 miles on its own at Glacier, Yellowstone, Teton, Badlands etc.
2014 Keystone Cougar 313RIL.- Bill and Carol Horton