So I figured it out. As "Rendering Resolution" was removed and much of this was moved into an "auto detect" function, there are ways to force the game to play below the limits of its auto-detected resolutions. Set your config files to the desired rendering resolution. Change your desktop to match that resolution. Lastly, if you have a nVidia card, use the nVidia Control Panel to override application settings with regards to scaling. Typically DayZ wants to play full screen regardless of aspect ratio (another setting that has been removed in recent patches. Sensing a theme here?). Using the nVidia control panel, you can tell it to override the scaling, preventing full screen. The game runs wonderfully for me at 800x600 (weak sh!t computer), however, DayZ wants to stretch it to widescreen format and the control panel will prevent that.