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Also, you can append before the divide and add, making the graph a bit cleaner :)
It's OpenGL vs DirectX coordinate system discrepancies most likely. DX is Microsoft only (Xbox & Windows)
That's quite strange. There might be some half-pixel offset issues, but I'm not quire sure. Try using the Scene UVs node and offset the UVs by half a pixel, using the screen parameters node.
That's a pretty good idea, I'll probably look at doing that after a few releases :)
This is a known issue caused.by infinite looping
Alright. Not sure what error you're getting, nor what could be the fault, given that I haven't looked into the terrain shaders yet
It could be because he accidentally left in two parentheses in the first edit, where it should have been one, after nornalLocal
This is more of a question for the forums, so, I'm closing this. Anyhow, here are some hints:

http://acegikmo.com/shaderforge/wiki/index.php?tit...
http://acegikmo.com/shaderforge/wiki/index.php?tit...

So what you probably want to do in this case, is to generate a gradient using the world position Y axis, if you want a gradient based on height :)