Area portals appear as solid area portals, not entities ( Area Portal visgroup, not Areaportals ). The Areaportals visgroup is here too but there's nothing in it so I assume the entities are simply not tied to brush anymore.
Another change is that all my nodraw textured surfaces are now playerclip textured.
Entities seem to be fine at first glance. Can't really tell until I compile and test the thing.
Also, every entity has a hammerid property.
edit: my occluders have lost their solids too. and an areaportal in water was textured with water texture.