I cannot understand if your issue is that that background of the exported image is black or that the image is blurred. If it is the background, you should keep in mind that you can control that color like so:
(var stream = File.Open(@
If the image in your opinion is blurred. Honestly I cannot decide if the provided image is blurred or not. I cannot even differentiate the links from the shapes. The problem is that the diagram is huge. This forces all shapes to be shrinked so much that they are unreadable. The approach to address this would be to export the diagram to a larger image so that there is enough space for all shapes.
Pavel R. Pavlov
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