What he said. Download the RAR or ZIP file, or sometimes even the C4D/Fractal stick itself. Extract them anywhere, preferably your personal GFX folders. Once that's done, you've successfully extracted them.
The next step is "installing" them. There's actually no such thing as installign C4D. You just click and drag the C4D, or open in it a new canvas, cut it, then paste it in your current canvas. All you need to do, I re-state, is click and drag the C4D/Fractal stock ONTO your current canvas.