Further to another post, I believe there are airports that will not display or load into the navigation display unit. This means that if you are on the ground and you require to zoom in to help with taxiing, you cant as the airport will not load. This error also prevents setting up BTV if your arrival airport is one that will not load.
This with a Navigraph subscription and setup correctly within the OIS and system (other maps load, as do terminal charts)
For me, EGLL (Heathrow) will not load.
What other airports are failing to load, how big is this issue?