@Boz For the next version the editor will work with versions higher than 8. (I use version 8.3 and everything is fine)
For the next version, I merged the terrain editor with the zone editor rather than having the terrain editor separate. It’s much more convenient to use now.
I took the opportunity to added all the different tools (tree editor, cave editor, script editor and quest editor) directly in the game editor rather than in separate editors in the Project Manager.
So, everything is in the Game Editor for easier access.

