Hi Umberto. P3D v5.3HF2. I created a walkway from the terminal building to a point close to the front left of my PMDG737-900.
During the operation I opened front and rear left doors plus cargo aft and forward.
But that didn’t satisfy GSX which wanted right forward and aft doors open too. Why? I haven’t requested catering services. This appears to be linked to pax walking to the aircraft rather than using a jetway or bus.