I downloaded (after much consternation) DJI Assistant 2 in order to calibrate the vision system on my M2P. I get to the part where you're supposed to point the camera at the computer screen and nothing happens...no pattern to follow, nothing. It also said it couldn't tell what size my screen is (using MacBook air), so i entered 1440x900 in the box but got no OK message and went on. Any ideas?