V8 - Blocking Volumes on Vanes above 8. Should help, but those meshes are a pain because of the shape (often I'll just use DrawScale=1.01 to make the BV a bit bigger, but here because of the U shape it messes it up. But should be better.
Also, moved the Blocking volume over the top back... you'll still likely get blocked by terrain (except maybe wyvern which has high jump) from going directly over, but it was annoying to hit the invisbile wall.