How to model skies in BTB?

[Kalmykov]

Hello people.
I'm new to all this modelling thing but I need to build some very simple tracks for Racer for my university project. I have some problem with modelling a proper sky. I have no sky currently so the track looks like this.
http://www.racedepartment.com/forum/attachments/sky13-jpg.39781/

I was hoping to use the textures from another Racer track, Carlswood. Yet I can't figure out how to do this.
Can anyone give me a link to some sort of tutorial? Or, if you can, write it down here. I would appreciate if you make it very simple and thorough (screenshots can help too) because, as I've mentioned before, I know almost nothing about track building.
Thank you

 

[Kennett Ylitalo]

Don't know how many knows about Racer here, it's been mostly rF, Race07 and RBR.. rF and Race uses skydome that's mapped with a 360 view of the sky in specially named DDS textures. So if its the same type of system, BTB should make the dome but is probably missing the corresponding texture or it's simply erroneously named.