I found a handy script for the sky. I'm using it also atm and everything works fine now.


All you have to do is add this below the includes (and of course make your own sky images).

sky cube
{
type=<sky3021.tga>; //the filename of the sky. change according to the sky you want
layer=2;
z=20; //change this if the skycube is displayed too high or too low
material=mat_sky;
flags=cube,visible;
}