HaloMods "Classic" Read-only Archive

ne 1 plz help

ok, im a n00b so plz dont flame me but how do u get the mod into the map,for instince i wanted the city blood gultch thing and i thought it was going to be a .rar file but it was like a ppf or somting how or were do i put the file that i DL off this site in my comps directory
Thanks 4 the help..[/b]