Downloading and unzipping the files into your game 

Objects:

Extract the file inside the zip file into: My Documents\EA Games\The Sims 2\Downloads Recolored objects which do not have a color option in the original game will only appear in your game if you have the Color Options Enabler installed

Make sure you have the latest update of CEP!

Houses:

Open the zip file and double click on the file.
It will automatically be extracted to the right place in your game.

Walls / Floors:

Extract the file inside the zip file into: My Documents\EA Games\The Sims 2\Downloads