Some screensaver depend on the 3D capabilities of your graphics card. In some cases, you will encounter errors that the screensaver does not support the current graphics card installed in your system or no errors at all. In some cases, certain screensavers don't have the possibility to be configured and such when you press the config button it does nothing. Also, to see the screensaver in effect, try to set up a small timer, like 1 minute and then don't move anything on the screen.
