Ah, I see. That's not what I thought you were looking for then. I really liked the fully darkened blank screen screensaver as all the other ones are just so distracting (I can't understand why Apple wouldn't include it as an option). Often I am reading academic texts at my desk and need to concentrate but don't need my computer for that period and need it to disappear into the background, so to speak. Anyway, I've solved my problem and hope you find a developer who helps you solve yours. By the way, you can still have the clock showing on the screen with my solution. It's just that it doesn't move, so it might be a strain on those particular pixels it uses I suppose. Good luck!
Nigel