If you mean the skybox, then yes, it is possible to change it into an actual skybox. If you mean the skybox for the lower half of the map, then no, it is not possible to change. Unfortunately, I can't tell you exactly how to change the skybox, because I don't have access to the editor at the moment.
@zeldarules28:
Use "Set Background model". I haven't tested it yet but the description point it is related to skybox.
According to another thread I've read sometimes ago, only Aïur sky is working with this action.
As the title says, "Is it possible to change the background color?" .
@FraindorX: Go
You'll need to be a little more specific on which background you want to change.
If you mean the skybox, then yes, it is possible to change it into an actual skybox. If you mean the skybox for the lower half of the map, then no, it is not possible to change. Unfortunately, I can't tell you exactly how to change the skybox, because I don't have access to the editor at the moment.
It was not obvious at all. And I think you can. But Im not sure how. Take a look at terrain texture sets, somebody did a tutorial.