I'm sure your WinRAR is working fine. Some things to check:
1. You are putting the .package files into My Documents\EA Games\The Sims 2\Downloads
2. Downloads is spelled with a capital 'D'. Lower case will block Bodyshop type CC but not objects CC.
3. In Options, Game Options, the flag is set to show custom content in the catalog.
Yes. I don't have any problems with getting custom content to show up and I notice I don't have any problems with zip files showing up, but for some reason not ALL of my Rar files will show up.