There is no downscaling in WME, but you might consider using WMElite if you have a 2D game. WMElite will not be a 100% drop in replacement for WME, but it is behaving close to WME on Windows (and other platforms). There is more required than to simply downscale the screen to have it still look nice, thus there is some extra effort put into WMElite. This could all be ported to WME as well, assuming you find somebody that knows how to implement this using DirectX.