Using blender2crystal it should be possible to export a terrain created in blender (there are blender plugins to do that).
, there are a few "terrain" examples there.
One can also study/copy one the CS/data/terrain?/ map and go from there, but that's not ideal.
I believe the heightmapgen
tool found in CS creates heightmap and required stuff from a regular mesh.
Finally, there's the basemapgen
which is quite useful to generate the basemap (texture as seen from great distance) for a terrain,
based on the materials from the material map.
The prefered way is indeed the Blender & blender2crystal way. This allows easy modifications.