I gave you the link to a mod installation guide in my yesterday's post above. Take the time to read it: http://www.lucasforums.com/showthread.php?t=143422
It should answer your questions and should you have read it, you would have also found the information concerning .rar files .
And please stop posting comments like "that retarded mod": they are offending and gratuitous. If you have comments concerning a mod in particular, post them in the appropriate thread and use constructive criticism. Redhawke worked very hard on those mods.
Edit: as for Redhawke's mods, the problem is certainly a bad installation as those mods work fine.