I've read this for help: http://www.morrowind-oblivion.com/morrowind_cs4_tutorial.php

...but I still can't raise or lower my landscape. I hold down the left mouse button while moving the mouse up or down and nothing happens.
http://img130.imageshack.us/img130/9577/12385662.jpg

What gives?

I don't know if this is the problem, but, when i am playing in the Construction Set, i can only alter the land that i am in (e.g. Ashlands 0,2) not any other land that is in my view.

This probably isn't the problem, but it is for me some times

This question came up about 10 days ago. First, make sure your Land Sensitivity Multiplier (in the Landscape Editor) is not set to 0. I believe the default is 1.00. If that isn't the problem, try reading http://www.gamesas.com/index.php?/topic/1079496-unable-to-make-new-land/ thread.

If you don't know how to use involved instructions, If i were you, I would un-install and reinstall to get it to work. When it asks if you want to remove the mods and pluggins, choose no. But that has always worked for me!

lol, ah there was the problem. Somehow, in preferences, my multiplier was set to zero. So I put it to 1.00 and it works fine now. Thanks Maneki!

You are welcome! Based on your experience and the others a few days ago, this seems to be a common occurrence lately... But the good thing is it's an easy problem to fix.