Used tools:4ds Tools 2.1,Mesh to Terrain,Relief Terrain Pack 3.2.

Tutorials and documentation of RTP 3.2 here.

About Mesh2Terrain.

How to prepare textures. (Tutorial)

You should have 3 copies of one texture:

1)Color + spec.(RGB+Alpha) Alpha channel is reflection map

2)Normal map u can make by Nvidia plugin for photoshop

3)Height map is a usual grayscale.