Using additive scene loading, I dynamically add and remove NavMeshes into the game at runtime. However, sometimes I want to re-position the newly added NavMeshes. Is it possible to do this? To move NavMeshes at runtime? Alternatively, is it possible to move an entire instantiated scene?
Yes you can! Look at this link:
http://forum.unity3d.com/threads/generating-a-navmesh-from-a-terrain-partial-code-available.38102/
As of Unity version 5.3.4, translating a NavMesh isn’t possible, nor is it possible to translate an entire Scene object. Consider other solutions to pathfinding. A lot of plugins on the asset store exist, one that is particularly excellent is the A* Pathfinding Project.