If you get the following error "Unknown build error, 'Input string was not in a correct format. Line 60 Position 120.'" Make sure that you are closing your {} on Binding statements. This line will give you an error: <HierarchicalDataTemplate x:Key="itemTag" ItemsSource ="{Binding Path=ChildNodes" />
I've highlighted the ItemsSource in red because that's the offending bit of code, and I just want to save everyone a little bit of time. Possibly this could be a feature request to the Cider team to keep me from "fat fingering" code. Maybe that's what I get for typing in straight XAML.