Fixed in 1.4.
In the Thystes Fortress, a couple of the doorways leading from the ramparts are too low to fit through without crouching. The first is the doorway from the southeastern ramparts into the latrine room. The second is the doorway from the central tower structure into the ramparts that run west-east through the center of the map.
This was tested with the fighter. I don’t know if the other classes have different heights like in some mods.