Final Cut Pro doesn't load various elements downloaded

More often than not when I download and load an element downloaded from here (generators and titles) it doesn’t work with Final Cut Pro. The last one (that I really need to use) is the Photographic Logo Reveal file. I moved the files into the appropriate folder and it shows inside Final Cut Pro, but the generator doesn’t load. I get a red screen, with a “2,” and a caution symbol. What can I to remedy this situation, and in general why don’t the files don’t work all the time?