First, try not to write in all capitals, because it's hard to read, and it's considered rude on the internet.
If you see the Trial airports menu, it means GSX is not activated so, check in the Addon Manager first, and see if the Addon Manager reports it as "In Trial" or "Active"
If the Addon Manager says it's in Trial, you only need to activate it.
If the Addon Manager says it's Active, then it's Active so, it's possible you are mistakenly running FSX or another addon that starts with or launches FSX, in "Compatibility mode", like XP mode under Windows 7 or similar.
Check you don't run FSX into a “Compatibility” mode, like XP or Vista or Windows 7, under Windows 8. Turn off any compatibility modes for the FSX.EXE, which is how FSX is installed by default.