Custom XML handling by Grid with Smart Rendering

I would like to use the Custom XML format to load in a Grid, instead of using datastore. Because, I need to use the treegrid as well. With the example provided, I can’t use custom XML with Smart Rendering.
I would like to load the XML like below format.

<data pos='0' total_count='72'>
    <item id="1071">
        <TITLE><![CDATA[The Town]]></TITLE>