Why do shorelines sometimes look strange (with bits of land seemingly out in the water or with the shoreline on the wrong side)?
(This issue does not apply to versions 6.10 and later.) Shorelines in the water result from the automatic shoreline placement getting confused when there is a complex pattern of water and land. Things like barrier islands can cause a lot of trouble. X-Plane draws a shoreline and water transition texture in the water tile that’s adjacent to a land tile. When the water/land pattern gets complicated this algorithm breaks down.