You need to handle the Breadcrumb.ConvertItem event and provide the proper trail from the "new" SelectedItem up to the RootItem. While the DataTemplates and Styles can be used to drill down the hierarchy, they cannot be used to work back up to the RootItem. Therefore, you have to perform this step by handling the ConvertItem event. In addition, this event can be used to convert to and from a string path.
Our Sample Browser shows how this is done in the "Breadcrumb File System" QuickStart under the Naviation section. In addition, there is a topic on this subject in our help file under "Actipro Navigation\Breadcrumb Features\Item Conversion".
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