By default they do not appear in the list after installation. To fix this (after you have installed it), you need to make sure 'xscreensaver -nosplash' and other instances are closed and run this command from a terminal "/usr/bin/rss-glx_install" then they will appear in the list to select.
añade nuevos salvapantallas 3d a tu colección ya existente / Add new screensavers at your own collection