The diagram expects a HierarchicalDataSource or in the latest version - a flat dataSource and conectionsDataSource. If you wish to use the edit window, then you should update the used version and set the connectionsDataSource as well. Also, in this scenario the diagram requires the new shape items to be synced and the Id to be assigned from the crate operation in order to render the shapes so you will need to implement the transport operations. I updated the example
to demonstrate this scenario.
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