Ahhh... my OCD cant handle the new base building deforming the terrain permanently.
In previous version u could place a cubic room, and delete it that the terrain would go back to normal and grass would grow again, in this version the cubic rooms deform the terrain under it and grass will not grow again.
The good thing is that in this version you can build a base underground, but i love my grass intact, so i liked the base bulding from the old version a little more.
My solution for now is making a save, and build, if i make a mistake i just have to reload and build all over again. My precious grass