I messed around with that world streamer so you can move around etc.
The GFX mesh has some seams though and the the KDTree ends after a certain point, not sure how to fix those. modifiedterraingenthing.blend (3.6 MB)
its a way to generate a procedural terrain between control meshes (foundations / roads /trails) using mathutils noise, or a heightmap by parsing a image to a list.