Unofficial Skyrim Special Edition Patch

Triangle #4 edge 0-1 is missing its connection to triangle #56 edge 1-2 and vice versa. Together with adjacent changes, this causes Hearthfires.esm to lose many Found flags (present in Skyrim.esm), meaning the navmesh algorithm cannot traverse the triangles.

Also, best to complete the preferred flags. Originally I'd thought it was the missing preferred that was causing the problems, but really it was probably the missing Found flags. Nevertheless, still useful to attach the preferred flags from exterior01 all the way to the road.