Undo Doesn't Replace Everything

When I delete a node with multiple links and then call the undo method not all the links come back. Not doing anything special with this just using the built in UndoManager.

Could you provide more details? Certainly that doesn’t happen when I try deleting nodes and undoing in Demo1.
Are there any side-effects occuring during the undo that would break the undo process?
It would be tedious, but you could try stepping through the undo() call, to make sure only those things that should happen are happening.