I see. So as long as the wing positions are valid to the mesh used there shouldn't be any problems with modifying it, and as long as i export it as an .obj file the game will be able to use it.
When i tried importing a custom model the wing positions were off so it would just crash, that must've been it.
I also wanted to try making a VTOL style aircraft and maybe make the wheels pivot (using the rudder controls) to make planes more maneuverable on the "ground" but I don't think that's possible without digging into the code.
Thanks