Copy the Scenes folder into Base.rte, if you have an edited SceneIndex.ini, Put the following into it somewhere:

//Zero-G:
IncludeFile = Base.rte/Scenes/Scenes/Grass Plains 1 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Grass Plains 2 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Desert 1 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Forest 1 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Mountains 1 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Mountains 2 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Tundra 1 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Tundra 2 Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Caves 1 Zero-G.ini

IncludeFile = Base.rte/Scenes/Scenes/Horiz Land Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Rich Lands Zero-G.ini
IncludeFile = Base.rte/Scenes/Scenes/Ketanot Hills Zero-G.ini

Then add the Scenes folder that is inside the Scenes folder (if that makes sense)