http://www.ediy.co.nz/andres/Temp/TresEd_2003-09-09.zip
I've reworked the terrain editing tools, in Area mode can 'paint' with left drag, and (instead of the crappy Set) is Level mode: Right drag creates level areas as before, but best is the left drag, which is a sort of smoothing effect (actually more of a 'flatten'). Very useful for creating roads/pathways up hills/cliffs.
Editing in progress:
http://www.ediy.co.nz/andres/Temp/TresEd012.gif
The completed testscene Matterhorn:
http://www.ediy.co.nz/andres/Temp/TPass014.jpg and
http://www.ediy.co.nz/andres/Temp/TPass015.jpg
My strategy: create the general shape of hill and cliff with Paint tool(doing a left drag) and Level (doing a right drag). Then while in Level mode, turn on "auto-subdivide", set radius=0, feather=2, and right drag back and forth along the pathway I'm creating. With a bit of practice, it turned out to be easier than I thought to create pathways.
Also can print out animation script frame for camera/selected instance (see readme)