Terrain generation is located in the Terrain Kit folder of the package. The terrain itself is generated using the CreateTerrain script, and the GUI is in the ExampleTerrainGUI script. The scene itself actually uses a pre-generated terrain. It's only re-created if you use the menu.
And in the future, please stick to one post. Two posts and a PM asking the same thing is not going to get my attention any better than a single post.