Hello Paul Ashton,
The TreeList (and Silverlight controls in general) will not bind as easily to XML or dynamic (as in DLR) objects.
You may be able to use ValueConverters in the DataBindings in the CellTemplates of the TreeList that will extract the value from the XML in a way you expect.
Can you describe your scenario in a little more detail? Then possibly we can think of a more specific suggestion that will work for you.
the Telerik team
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