I have installed two of the 7" touch screens on two separate pcDuino3 boards. They both give me the same problem which appears to be a refresh issue. If the open program is moved by left-clicking with the mouse and trying to move the window, the window does indeed move but you can't see it. Instead, the window seems to shrink by the amount it was moved. Minimizing and restoring the window will redisplay the window properly in the new location. For some reason, LXTerminal does not exhibit this problem but I believe all the other programs do. This problem did not occur using the HDMI display port.
In the same vein, programs opened in Leafpad that are more than one page long do not scroll properly. Several lines at the top or bottom of the window, depending on which way you are scrolling, remain stationary.
Obviously, this is very frustrating and currently the screen is unusable unless a solution is found. Without this screen working it essentially makes the pcDuino3 unusable for my application as well.
I noticed one other user had this same problem a couple of years ago but didn't seem to get it resolved. Can anyone shed more light on this?