Immediately after updating to the most recent version of Multiwall, my left (Primary) monitor has been left a permanently black screen. After messing around with settings I have determined that this only happens when my displays are set to individual, auto cycle is on, and auto-apply is on. If I manually change the primary's wallpaper under the "Wallpaper" tab, then it sets it properly, but once the auto cycle ticks over it goes back to being a blank screen.
Multiwall is still registering both monitors, and I prior to this I had no problems with the program at all.