So far, I have one theory. Take a look at CliffMeshData.xml, after I did a bunch of random tinkering and experimentation with Terrain Cliff Meshes in the Data Editor:
Code
<?xml version="1.0" encoding="us-ascii"?>
<Catalog>
<CCliffMesh id="CliffNatural02">
<ModelPath value="Assets\Cliffs\CliffNatural0\"/>
<CliffHeights index="0" value="3.999700"/>
<CliffHeights index="1" value="3.999800"/>
<CliffHeights index="2" value="3.999900"/>
</CCliffMesh>
<CCliffMesh id="CliffNatural022">
<ModelPath value="Assets\Cliffs\CliffNatural0\"/>
<CliffHeights index="0" value="-8.000000"/>
<CliffHeights index="1" value="0.000000"/>
<CliffHeights index="2" value="2.000000"/>
</CCliffMesh>
</Catalog>
<Catalog>
<CCliffMesh id="CliffNatural02">
<ModelPath value="Assets\Cliffs\CliffNatural0\"/>
<CliffHeights index="0" value="3.999700"/>
<CliffHeights index="1" value="3.999800"/>
<CliffHeights index="2" value="3.999900"/>
</CCliffMesh>
<CCliffMesh id="CliffNatural022">
<ModelPath value="Assets\Cliffs\CliffNatural0\"/>
<CliffHeights index="0" value="-8.000000"/>
<CliffHeights index="1" value="0.000000"/>
<CliffHeights index="2" value="2.000000"/>
</CCliffMesh>
</Catalog>
What if I could simply add more CliffHeights tags (with higher indices) to a CCliffMesh? Well, there's just one problem (aside from the fact that I'm not sure if it'll even work): GalaxyEdit's Import module does not allow you to replace "reserved" files, and CliffMeshData.xml is reserved.
So for me to test this theory, I need to know: how do I replace files that GE is trying to protect?
None.