Unzip and drop into your downloads folder. Or if you have subfolders your hacks subfolder. It should work from there, it does in my game. The patch for OFB will automatically install when you install OFB, or you can dl it from the main website. I wouldn't start up my game without patching first!
When I installed OFB, it did not download the patch and install it. I had to install it myself. Even with broadband, it took some time to download it, so I am sure I would have known if it was downloading it. It said it was checking if my installation was up-to-date, but it came back immediately and said it was.
I am installing this fix right away. I thought it was strange that some of my sims were working forever and having nothing to show for it.