In a VS 19 project the main form has a pictureBox control. For test purposes I used a button to add a map image from a png file and another button to add small rectangles representing waypoints, from co-ordinate data displayed in a textBox control on the form. This worked perfectly by clicking the buttons in order. When I decided to combine the process with a single click, however, the map terrain was visible but not the waypoints. If I bypassed the loading of the map, the waypoints were displayed. Any suggestions?