Downloading from a fansite? It sounds like a internet speed and/or busy server issue.
As for rar files… Rar files don’t show up by themselves. They’re like a compressed file with stuff inside it. You have to open them up with the typical software that opens up Rar/Zip files and then put the appropriate files into the appropriate Sims sub-folder, just like any Sims games (or other moddable games like the Elder Scrolls games or Persona 4 game, etc, with the Mods sub folder and the other various other sub folders).
