I see no reason why ghost buildings are not included. Programming issues, perhaps?
This is one of the most popular QOL mods out there and used by players who want to design new efficient bases. Ghost buildings are used to design things as well. So ghost buildings and this mod would lightly speaking go hand in hand.
As it is now, I have to design everything in a creative map with editor, so my blueprints or copy-pastes are instantly placed instead of ghosted..