What I want to do:

Have a pre-logon screensaver running on every pc in school, something like the my pictures screensaver, but have the screensaver point to a shared folder so that all I have to do is change the images within one folder.

What I know how to do:

I know how to change the default screensaver, but thats about it. In the registry I can set the screensaver to ssmypics.scr but then it tries to look at a folder which isnt there and changing it whilst logged in as admin doesnt make any difference.