I have the feeling that you have not even tried to create a sample project on your side using the steps and the code from the article. The code is fully runnable and all you need to do is to create an empty project and paste the code in your main view.
If you have tried to create a sample project using the article you should have noticed that even though the location of the ellipse does not origin from its center, its position remains constant. No recalculation of its radius or location is needed. Once placed on the layer it is automatically sized based on the zoom level of the RadMap.
Pavel R. Pavlov
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