HaloMods "Classic" Read-only Archive

I have 2 questions
1. how do i add alot of fog 2 bg
2. is it possible to add brand new scenery modled in 3ds max into game without lossing any other scnery if so how?

o i get it but how do i add fog to bg i imported fog from 343 guilty spark changed its ID with swap edian and then in hex hit find gof and then were it said FFFFFFFF i put the new number yet the fog wont show