As explained so many times, nothing in GSX ( in MSFS ) has any control whether the jetway will work or not. What GSX does in MSFS, it's just sending a key trigger command to the sim to operate the jetway but then, everything happens inside MSFS and GSX has no control over the docking process.
The only thing that affects if a jetway works or not are:
- Your parking position
- The airplane door configuration in relationship to your parking position
- How the jetway is placed in the airport
- How the jetway is modeled
What you CAN do in GSX to affect jetway resolution INDIRECTLY, is customize the Stop position, so GSX will guide you in a position where the jetway will hopefully work. That's why the GSX parking customization has a JETWAY TEST function ( NumPad 5 while editing the STOP position ), which will try the jetway, so you can adjust the Stop position to make it work better.