I have this set of meshes where the ground, roads, and sidewalks are separate tiled meshes. Whenever I try to add a nav modifier to the ground’s static mesh actor, the entire tile becomes receives the modifier, even where there is not a ground mesh. I had enabled complex colliders in my project settings, but it appears that the navmesh is still using a simple bounding box to represent the mesh.
The following image shows the effect of toggling the center ground mesh as unwalkable. The surrounding ground meshes are selected to show that they are intersecting with the unwalkable area. Also note that the roads in the center tile are marked as unwalkable even though they do not have a nav modifier applied to them.
