No matter which boarding gate you are in, you will be prompted that it is too small.
This because you haven't read the manual, which offers you many explanations, and the many ways to deal with this:
- Page 11
GSX will warn you if a parking spot is either “too small for your aircraft”, or is already taken by an AI. However, a big change from previous versions is that will allow you to use it anyway.
- Page 33, the explanation of the "
Max Allowed Wingspan" parameter, which can be used if that previous message annoys you:
This option allows to override the parking radius in the airport .BGL, used to verify if a parking is too small to fit a certain parking. Sometimes, it’s possible a scenery has actual space available around a parking spot, but the scenery designer has specified a smaller radius for that parking spot, maybe for AI flow reasons, or to fix problems with default ground vehicles, or simply because of an oversight.
- Page 27, the explanation of the "
Ignore Wingspan when parking" global setting:
This option will disable the “Parking Too Small” warning. Note that, with this version, GSX will always allow to use a parking, even if it says it’s too small but, with this option, you can also disable the warning.
And the air bridge will not be able to align with the boarding gate.
That's because you are assuming GSX has any effect to the way Jetways work or not. It doesn't. The jetway animation is still controlled by the simulator, GSX only replaced its look but whether it will work or not, it only depends by the airplane and how is positioned in relationship with the jetway.
When using a third-party airport map, there will be repeated parking spaces.
That's also because you haven't read the manual, this time Page 7, which explain you should disable GSX Jetway replacement files for airports you have a 3rd party scenery for, and explain how the Config page works. Some sceneries will be automatically disabled by clicking the "Exclude 3rd party" button, others will require to be added manually to the Disabled list with their code.
No matter which method you use to Disable an airport you have a 3rd party scenery for, you MUST Disable it, otherwise it will happen exactly what you reported: double parking spots, because as the manual says, the Jetway replacement files supplied with GSX are only meant to be used for default airports.