The DMR registers all input as a Keyboard stroke, so the monitor waking up is unavoidable, I think. You could emulate "sleep" by using an allblack effects plug-in.
As far as AppleScript is concerned, download the latest version of the DMR software, it has full AppleScript support, and you can paste a script directly into the Control Panel. It's kinda buggy, though; I ended up saving my scripts as applets and mapping the DMR keys to them.
Good luck, I'd be interested to hear about any progress you make.