@Shadow Echo - the way you make your added terrain a different color than grey is to use the terrain analyzer! We made that change intentionally, to bring awareness to the "footprint" that you as the player have on the planet. Once you unlock terrain analyzers, you can sample any color of terrain you want and choose which color to apply to newly added terrain. It also solves a technical question about which color the terrain could be when adding, because the color data contained inside empty voxels doesn't always match the color of terrain you're extending. Random changing of colors while adding terrain feels kind of weird. In any case, once you've got a few colors available, I'd love to see how you decorate your base!