Hi Jose,
We have created the sample for using the ContextMenuAdv in TreeViewAdv control. ContextMenuAdv is available in the following NameSpace
xmlns:sync="clr-namespace:Syncfusion.Windows.Shared;assembly=Syncfusion.Shared.Silverlight"
Please refer the sample under the following location.
Regards,
Sakthi
TreeViewSiver_c877a25f.zip