Look on the left margin of the My Sims Realty main page and you'll see a button for Install Info. I downloaded mine just to my desktop, extracted the zipped file also to my desktop, then double clicked the Plumbob icon for that world. It automatically loaded it into the launcher and into the game. Then when you go to start a new game, that world is in the list with Riverview and Sunset Valley to choose. After I got it installed into the game, I deleted both icons from my desktop.