The NavMesh creates breaks at the wrong rotation if the mesh is using collision created from outside of UE4.
This is obvious in a lot of the market content with special collision created in maya/3dsmax
1. Create a top-down template project
2. Download and extract the attached file
3. Place the AncientRuins folder in the Content folder of the project
4. Place the Ruins_14 asset in the level
5. Show navigation
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