Oh… wait a second… did I miss something?
Do you mean that AI aircraft takeoff and land without AIG or FSLTL loaded, and it’s only their planes which don’t act properly?
Seems like that’s a problem with those packages then, not the airport based on that information. You’d have issues with default AI as well if there was a problem with the airport.
I have no experience with or knowledge of how those packages work, or what it means to “Only use the models”. Sure, there shouldn’t be an issue with the models, but, I’d have to look through those models then to determine if there’s anything about the planes that could be conflicting. It could be the radius of the parking spots isn’t big enough for those models to show up? Are they showing up in parking spots and just not taking off, or are you saying they are not showing up on the airport?
I’m confused by what your post means. What do you mean by “default does work with this setup for taxiing and takeoffs”? Default what?