Accidently added image on Interface... Result in a no method to capture mouse location over a BitMap... still testing the scroll-bar inside the testImage.py interface. Having problem to see your image, just change the size of the Main window. Enlarge it until you get a black region, mouse will start to report position inside task-bar... Denoted it might be possible to move the Bitmap to a lower index or possibly get the mouse from somethign else than event.GetPositionTuple() , or focus problems...