Hello,
I've found something I don't really understand :
When I don't set Width and Height in the Silverlight MapControl, then I get a NullReferenceException while calling map.Refresh() method.
Actually, the map.CurrentExtent property is null, and I cannot set it to any value. When I make map.CurrentExtent = new RectangleShape(471561, 305539, 858543, 51620); then the CurrentExtent is still null, and I get no message.
This behavior looks a bit strange, isn't it ?
Guillaume.