[Solved] How do I lower my terrain height like this?

[X-Death]

How do I lower my terrain height like this?
http://img685.imageshack.us/img685/4342/advancedterrain.png

Displayed in the screen shot

How can you lower the terrain so far like that?

 

[Chaosy]

download this http://www.hiveworkshop.com/forums/pastebin.php?id=6fmhzt fixed by maker and use the raise tool

 

[Kala]

And Plateau tool to make straight walls.

 

[X-Death]

Thank you! =D