Unable to save any modifications with GSX2 in P3D 5.4 - The apply button will change to grayed out in a nano second.
I am able to go into the customization mode and when I hit the "Y" slew (Exit from editor) the apply mode button is grayed out.
All I did was change the parking and hit the Y key and the apply option is grayed out. Had same issue with your KMEM.
BTW, I did disable the default Jetways this airport has.
If I use the options for a logo for the jetway or type of jetway then I can use the APPLY button. If I change the parking, no apply option.
