From this and your other question, it seems you misunderstood what Enabling/Disabling an airport is used for.
It's not used to "Enable" GSX on a certain airport, because GSX is always enabled.
Instead, moving a jetway replacement file on the Disable column is made to PREVENT GSX from replacing jetways on a 3rd party airport, and it's not really something you can decide: GSX jetway replacement files are only meant to replace jetways at default airports, you can't (and you shouldn't) try to replace jetways on a 3rd party airport with GSX jetways because, even if they might visually appear, they will never work correctly, since they are assigned to a parking that is different, so nothing will work and, by keeping a jetway replacement file Enabled if you have an add-on airport, will introduce a scenery conflict, with double parking spots and other issues.
Normally, when you install or update GSX, all your 3rd party airports will be detected and automatically added to the Disabled list, and you should keep them there. Some airports (mostly freeware) that might not conform to the standard naming convention used in the Marketplace of developer-airport-ICAO-airportname will not be detected automatically, that's why you have the ability to Disable them manually, but you still must Disable them.