Got it working with your two suggestions. Thanks! So with windowed, non-full screen mode, radar placed in top-left and resized about midway so that lower-right of radar is visible/selectable in settings pane, it calibrated. Since then, I've been able to move the radar back to lower right and return to full screen mode with the radar still tracking at 100%. If it gives me troubles, I'll returby Max Poorboy Power - Issue Troubleshooting
I'm having the same problem. I'm attaching screenshots of the settings window after each step. After picking the bottom-right pixel, it shows a bar of graphics and mostly a white block and returns to step 1. The bar at right is red the whole time. I am running windows 10 with dual screens, game is on main monitor @ 2560x1440. All the settings for the game are the way requested in instructioby Max Poorboy Power - Issue Troubleshooting