NavMeshSurface Min Region Area

I've noticed that the NavMeshSurface component does not have a Min Region Area value. This value exists in the global Navigation inspector, but doesn't seem to affect the NavMeshSurface...

The problem I'm having is that I have NavMeshObstacles that are smaller than 1 unit, and it seems that the NavMeshSurface won't carve out smaller than 1 unit.

Here is a sphere at 1.0f scale:

Here is a sphere at 0.5f scale:


Is this a known limitation? Or am I overlooking something? How can I get my carve out to be tighter around objects smaller than 1 unit?

 

You're misunderstanding what the Min Region Area does. Say you have a platform of 1 square unit in size, then the NavMeshBuilder will or will not consider that platform for building depending on the Min Region Area value.
This will also cause narrow passageways to be completely unwalkable in some cases, regardless of agent size.
As for the obstacle size, I am not finding much but it seems you're hitting a limitation there, indeed.