Resurrecting b/c of a easier way...
...download below zip, unzip and move shortcuts to desktop. Attachment 123445
Whats cool is you can choose any of the 4 ms default screensavers and it Won't change your default in themes!
Don't want to wait for SS to start,
...Just click and the screensaver shortcut will start and run for the pre-determined time.
Should be good for ALL Flavors of Windows 7 & 32/64bit. Attachment 123446