Railworks America

I would like to know how to customize, my own sound dome in RW. I would like to add some sounds for a highway, and some better railyard and city sounds. Can anyone give me a little advice on how to do that? Also. Can I change the size and scope of the sound domes?

Thanks

I don't know of a possible way to do this, but I wish I knew of a way because I'd like to do the same thing.

Perhaps GreatNorthernor might know of a way to do this.