Code

System.ArgumentOutOfRangeException was unhandled
  Message="Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index"
  ParamName="index"
  Source="mscorlib"
  StackTrace:
       at System.Collections.CollectionBase.System.Collections.IList.get_Item(Int32 index)
       at MindFusion.Diagramming.PointCollection.get_Item(Int32 index)
       at MindFusion.Diagramming.DiagramLink.x5fcd47acc4164137()
       at MindFusion.Diagramming.DiagramLink.xd433eaf1292c9575()
       at MindFusion.Diagramming.DiagramLink.x0d5905a18dc24aa7(Boolean x1c5ff8c3c1ac16ad)
       at MindFusion.Diagramming.DiagramLink.UpdateFromPoints(Boolean updateGroups, Boolean updateSegmentCount)
       at MindFusion.Diagramming.DiagramLink.UpdateFromPoints(Boolean updateGroups)
       at MindFusion.Diagramming.DiagramLink.UpdateFromPoints()
       at MindFusion.Diagramming.Layout.x3462aa19b03aac15.xe47b2712dbae7a09()
       at MindFusion.Diagramming.Layout.x3462aa19b03aac15.x0360c0152e0fc04b(ArrayList x6fa2570084b2ad39)
       at MindFusion.Layout.x0bd7aa907b5c2ae1.xa80296b5ce0aad9d(x82e1bd820ac7ff15 x9fc3ee03a439f6f0, ArrayList xd9cc9787b074c77c)
       at MindFusion.Layout.x0bd7aa907b5c2ae1.x638e91bbe99a128d(x82e1bd820ac7ff15 x9fc3ee03a439f6f0, Single xd4d7bd59bc0483e3)
       at MindFusion.Layout.xabd66bcda3e8fc57.x8d75079465097c70(x0bd7aa907b5c2ae1 x6b631e0009a9deea, Boolean x4c8d8e849653d454, x01a1fee0f328037a xf4336cad79ab23b5)
       at MindFusion.Layout.xabd66bcda3e8fc57.x0bd7aa907b5c2ae1(Boolean x4c8d8e849653d454)
       at MindFusion.Diagramming.Layout.FlowLayout.BendLinks(Diagram diagram)
       at MindFusion.Diagramming.Layout.FlowLayout.x91cb73cecf8b5941(Diagram x8b62359f01cfd806)
       at MindFusion.Diagramming.Layout.FlowLayout.Arrange(Diagram diagram, DiagramItemCollection items, RectangleF[] laneBorders)
       at MindFusion.Diagramming.Layout.FlowLayout.Arrange(Diagram diagram, DiagramItemCollection items)
       at MindFusion.Diagramming.Layout.Layout.Arrange(Diagram diagram)
       at VisVoice.Form1.butLayoutFlow1_Click(Object sender, EventArgs e)
       at System.Windows.Forms.Control.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnClick(EventArgs e)
       at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
       at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
       at System.Windows.Forms.Control.WndProc(Message& m)
       at System.Windows.Forms.ButtonBase.WndProc(Message& m)
       at System.Windows.Forms.Button.WndProc(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
       at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
       at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
       at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
       at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
       at System.Windows.Forms.Application.Run(ApplicationContext context)
       at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun()
       at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel()
       at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(String[] commandLine)
       at VisVoice.My.MyApplication.Main(String[] Args)
       at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
       at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
       at System.Runtime.Hosting.ManifestRunner.Run(Boolean checkAptModel)
       at System.Runtime.Hosting.ManifestRunner.ExecuteAsAssembly()
       at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext, String[] activationCustomData)
       at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext)
       at System.Activator.CreateInstance(ActivationContext activationContext)
       at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssemblyDebugInZone()
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException:
 

Code

rules.ConnectorRules.HorizontalBendOrientation = false;

or

rules.ConnectorRules.HorizontalBendOrientation = true;