I'm not sure what a bodyshop package installer is- maybe you could direct her to download clean installer
However, if she's unzipping a package- she may just be getting a package file (.pkg)- if that is the case, instruct her to put the package file directly into her downloads folder.
Here is another useful resource
http://www.sims2wiki.info/wiki.php?title=Game_Help:Downloading_for_Fracking_Idiots