How to use the software and adding to the game?

I have downloaded Sims Studio and have tried to make it so vampire teeth and facial details, and alien eyes and skin to be available to human sims as well. I don't really know how to use this software and can't figure out how to make and install the content into the game. I clicked on the teeth and checked off that I want it available for all sims, but when I save it and put the .package into the mods folder it doesn't show up in the game. I'm not really good at this kind of thing and would really appreciate dumbed down, step-by-step help to get this to work. Thank you