Hi there !
As I'm not quite sure to know where the problem originates, I'm posting in misc.
I'm actually following Amaroth's english tutorials and I just started painting mountains and beach of a small test island.
On Noggit (Version compiled from repo a week ago), it looks like this :
But in game (WotLK), it looks like this with low shadows :
And like this with all parameters to ultra :
The first screen displaying noggit was made AFTER I saw the problem, so as you can see, most of the textures are fine, but there are still some stripes on the left that were definitely not there when I painted it, and the chunk near the circled cursor got pretty weird too.
Maybe it's a very simple problem I don't know (But I hope so !). I tried to search for it but I didn't find anything, so if you have any idea, please let me know.