have just downloaded the new version of CTS. "- on the first image, on the left is the CTS terrain shader, and on the right is the quixesl shader. From this view the CTS looks okay to me (a bit brighter then it should be, but okay)" Answer: Its brighter because its not metallic shader but specular. "Roughness map modified to 255 white, to make the sand look really rough, without any specular effect." Answer: Yes because smoothness = 1- roughness. So roughness =255 means smoothness = 0 so no reflections etc at all. Your AO in profile is =1? or in which value? Could you show global profile values?