I think someone said something about it being different for different terrains. That it's not possible to add a skybox on a map that didnt have one to begin with.I tried using the trigger Set Background Model, it doesn't seem to work (i.e. the sky is still pitch black).
I think it may be the problem with Far Clipping.
Can you explain that a bit more? Like how far should I set it in order to see the sky?