One of the problems I had with the ducky is that when typing a script on a target's pc it's really hard if there is a person in front of it. Instead of trying to create the command screen as small as possible so the targets won't see the screen, I've made it so big that they will think the monitor crashed or the cable fell out. The only thing you see now is a black screen and black text so the targets won't see any strings the ducky types. It also doesn't matter if the user clicks on somewhere on the screen with the mouse, because te whole screen is the command line.
Here is the payload: