Somewhat of a tip though, because the file is exported so large, you may want to consider a lower MPD and then subdividing in a 3rd party app. You can get near the same level of detail subdiving lower polys from Terragen. However, you must weld the OBJ prior to subdividing. Also, depending on how close a POV will be to the terrain you may need to adjust the Patch Size in you "Compute Terrain". If you're "Closer" you'll want lower values. If you're viewing from a distance, the default or higher values may serve better. Basiically this effects the UV scale, from what I understand, which then effects the textures/colours applied in 3rd party apps.