One of Gnome’s main philosphy is simplicity but in this endeavour, some things are a pain! For instance, Gnome’s pictures screensaver doesn’t let you specify what directory to look for pictures or photo’s to display (nor has the neat zooming and paning features of Xscreensaver’s Glslideshow). It expects all your pictures to be in a directory named Pictures in your home directory and this isn’t an easily configurable option, and it seems to not look for pictures in any sub-directories of the Pictures directory (all the pics need to be in one directory).
But you can use the xscreensaver’s screensaver with gnome-screensaver:
So once again I can use the Glslideshow screensaver without having to disable Gnome’s screensaver and configuring xscreensaver to auto start when I login. The only problem with this is I need to use the xscreensaver-demo command to configure xscreensaver’s screensaver. If you do this make sure you don’t start the xscreensaver daemon.