Navmesh issues

Hi everyone,

I already posted this under "Navigation", but received no replies. Thus, I am trying my luck here.

When I generate a navmesh for my terrain using the height mesh option ON, it seems to work well except on this area (see the first picture).
I actually have two doubts:

1. Why doesn't the height mesh show in pink when I press "Show HeightMesh" in the scene editor? In the pictures below, the option is ticked, but it does not show. Actually, it does show, but only on a small section of a static object (the red pipe). However, it seems to work because my AI is not moving very accurately on the ground (no spacing between the feet and the terrain mesh).

2. Why, in the first picture, an area of the navmesh wraps onto itself? This is causing problems with my AI.

 

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