Design Your Terrain by unknown author. If you recognize this text as written by you, contact us so we can give credit :)
My process with completely fictional terrain has been a sketch on paper → start blank project in designmap and raise lower terrain so its about what I want.
Apply some erosion and whatnot attributes with the design brush.
Generate → manually edit in sapphire (L3DT 3D editor).
Repeat until the terrain is nice.
Make custom climate → generate textures → import to Terrain Builder