I know this is somewhat of an old post, but you cannot get wallpaper on the iMID screen in a 2014 or later Civic with the DisplayAudio stereo. Swapping out the iMID display does nothing because the stereo determines where to display the wallpaper. The iMID is nothing but a secondary display for the stereo. So you are stuck with the wallpaper on the big 7" Display on the stereo, unless you wanted to yank the stereo and try to install 2013 stereo components, but that would just be stupid and very expensive.