How Do I Add An IC Identifier to Airport Listing?

Question

There is an airport in Mason City, IA that has the correct runways, buildings, hangers and numerous parked airplanes already installed in X-Plane 11. However the IC Identifier (KMCW) is not in the Listing of Supported Airports.  I can fly to the airport, land, take-off and land again, but I can't select it as a beginning airport. Can I add the identifier information myself? Or does Laminar Research need to add the Identifier in a future update?

Comments

Information in  "default apt dat/Earth nav  data/apt.dat" looks "normal" on the first glance:

1   1212 0 0 KMCW Mason City Municipal
1302 city Mason City
1302 country United States
1302 datum_lat 43.157805556
1302 datum_lon -93.33125
1302 faa_code MCW
1302 iata_code MCW
1302 icao_code KMCW
1302 region_code K3
1302 state Iowa
1302 transition_alt 18000
1302 transition_level 18000