Although supported by Leonardo there's still possibility to tune it. I added the rear stair to the configuration, which works perfectly. I remember having red from Leonardo, this shouldn't be possible due to GSX. For Ramp operations I don't see any problem. I didn't try what's happening on a jetway, the rear door closed.

Also to consider is the cargo doors mid and aft, that are close therefore the baggage trains collide. I had used the front cargo door. Maybe it was best to disable one cargo door and just do only the middle. At the moment, still both are active. Feel free to change. The code for the door has to be changed, if you want to use the fwd cargo door.

Make sure to let the gsx.cfg in the C:\Users\YourUserName\Documents\Prepar3D v4 Add-ons\MaddogX\SimObjects\Airplanes\MaddogX untouched. Put this into C:\Users\YourUserName\AppData\Roaming\Virtuali\Airplanes\MaddogX