Try "Restart and rebuild the airport cache" from the Couatl Settings menu, and pay attention of the airport cache is created, so you'll see an "airport cache loaded" at the end.
If the process doesn't start, or seems very long, it might be caused by the antivirus so configure the antivirus to add the following folders to the antivirus Exclusions:
- The main Addon Manager folder, where GSX is installed
- The main P3D installation folder
Then try again the cache rebuild