When the RadMap is panned with dragging or using the Navigator all markers are moved along with the map. This can be examined in the Overview demo of the Map
and in this screencast.
If the issue is that the Markers are not rendered in all possible places of the Map when paned too much to the right or left, as per to the correct position on all Maps. This is due to performance matters, so many markers would cause too much localization calculations and possibly affect the performance of the panning and zooming.
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