Hello.
I get an exception when I try to modify my diagramLink.
The exception is attached.The scenario is next:
When I create a node and a link that goes from and to that same node.
Then I arrange the diagram via my orthogonal router.
When I try to pull(modify) the link down from the dot in the right upper corner, this exception happens.
Any help?

Hi.
The stack trace is in the attachment.

The xml file as txt file is in the attachment

It throws this exception while i drag the link.
Both events LinkModified and LinkModifying are being used.
The latest version of wpf diagramming is being used.

private void DiagramLinkModified(object sender, LinkEventArgs e) {
                 var source = e.Link.Origin.Tag as ObservableState;
                 var target = e.Link.Destination.Tag as ObservableState;
                 var transition = e.Link.Tag as ObservableTransition;
                 transition.FromState = source;
                 transition.ToState = target;
                 IsDirty = true;
                 _diagramDrawing.ArrangeDiagram();
                 RaisePropertyChangedEvent(nameof(ComponentDiagram));
                 HandleLostFocus();
           }

private void DiagramLinkModifying(object sender, LinkValidationEventArgs e) {
                       if (e.Origin == null) {
                             e.Cancel = true;
                             return;
                       }
                       var source = e.Origin.Tag as ObservableState;
                       if (e.Destination != null) {
                             var destination = e.Destination.Tag as ObservableState;
                             if (destination == null) {
                                   e.Cancel = true;
                                   return;
                             }
                             var tmpSource = e.Link.Origin.Tag as ObservableState;
                             var tmpDestination = e.Link.Destination.Tag as ObservableState;
                             foreach (var transition in Transitions) {
                                   if (transition.FromState.Equals(tmpSource) && transition.ToState.Equals(tmpDestination) && transition.FunctionCode.Equals(e.Link.Text)) {
                                         continue;
                                   }
                                   if (transition.FromState.Equals(source) && transition.ToState.Equals(destination) && transition.FunctionCode.Equals(e.Link.Text)) {
                                         e.Cancel = true;
                                         return;
                                   }
                             }
                       }
           }

My desired width and height are not NaN, therefore it doesnt get in that if where i should get the coordinates.
I added an breakpoint into this function and the width and height are 39.5

The exception still happens.
The screenshot is in the attachment.
The exception is thrown in a viewModel that is initializing the viewModel where my diagram is.

The link strokeThickness is 1 but my e.link.Height and e.link.Width are NaN.
Regarding the control via TeamViewer and skype, it is not possible.