The docking port arms that swing down and extend when you dock are poking up and INTO the station sides/walls and when the arms rotate down they rotate right through the models walls as if they are not even there....
Hard to explain but if you dock at a Military outpost, just watch the rotating docking port arms and you will see them rotate the arms right through the walls/sides of the outpost model.
You are still able to dock but it appears the model needs a bit of a redesign with this visual issue.... unless all those walls are just holograms and I am imagining things...
