From the Manual
Customization files Priority
GSX follows a general priority rule, which is also valid for all Airplane customization
options that user-made content will always take precedence over internal data or
developer-supplied data. Airport customization are loaded according to the following
priority rules:
• A possible GSX internal customization for a scenery. They usually come with
FSDT airports, but not always, since GSX might come with some specific adjustment
for popular 3rd party sceneries as well. These settings are loaded first, so
they have the lowest priority.
• If an airport scenery comes with its own GSX .INI profile placed in the scenery
own folder, together with the other .BGLs that makes the airport, this file will
take precedence over any GSX internal data, adding to it.
• When users start to modify settings, the GSX .INI profile automatically created
in %APPDATA%\Virtuali\GSX\MSFS will get the highest possible priority, allowing
users to further customize a scenery which was already customized by the
original developer.
The name of the .BGL used to customize the scenery is listed in the [GENERAL]
section of the GSX .INI profile. It will include the complete path valid for your syste
mbut, don’t worry, there’s no need to edit it out before sharing your work, since
GSX will only use the .BGL filename, and will ignore the full path altogether, it
has been designed like this exactly to facilitate sharing of GSX .INI profiles without
worrying about different paths. As long the currently active .BGL matches the
name referenced in the .INI file, the .INI will be loaded by GSX, no matter the path
