How Do I Create a Screen Saver That Uses Shared Photos??

I have a pretty simple request here, or at least I think it should be pretty simple. My family uses a shared photo stream so that we can all see what everybody is up to without sending a bunch of individual messages.

I'm going to use a screen saver that displays photos but the tricky part is...I'd like the family's shared stream to be the source for all the photos.

Previously, I went into iPhoto and just selected all of the photos from the stream, dragged them into a desktop folder, and set this as the source for the screen saver. The only problem with this method is that whenever a new photo is added, it won't show up in the screen saver (obviously). That's why I'd like to set the shared photos as the source.

Is there a simple way to do this and set the shared photos as the screen saver source?? I would even settle for doing the alternate method that I described in the last paragraph, but I can't even figure out how to do this with the new "Photos" app...

PLEASE HELP!! Thanks in advance...

Pete