This how-to covers how to get the SV2020 saves into your game.
I'm using Chocolate as an example.
Hopefully this helps explain how to extract the game save file and load it into your game. This how-to is a companion article to Jaga's install instructions that can be found here.
1. Download Chocolate to your desktop. (SV2020_Chocolate_2.0.sims3.zip)
Worlds Download Page
2. Copy the zipped file to your Sims 3 Saves folder.
--- > Documents\Electronic Arts\The Sims 3\Saves
3a. Unzip the file by Right-clicking the file and selecting Extract All.
3b. A popup menu will appear. You can uncheck show extracted files when complete. Click Extract.
4. You will see both the zipped file and the save file. You can now delete the zip file.
5. Now to check to make sure it's showing up in the Sims 3 Main Menu.
Load the game to the main menu. There you should see a silhouette of a family when choosen, and a silhouette of a house. This is because you have not chosen a family to play yet.
When you have chosen a family and saved it, it should look something like this: