Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: Group iterator not in range

[friends110110]

trafficstars

when I set the configuration then I click left or right, the program throw exception : Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: Group iterator not in range at com.graphbuilder.curve.BSpline.appendTo(BSpline.java:286) at ControlPathPanel.paint(ControlPathPanel.java:364) at javax.swing.JComponent.paintToOffscreen(JComponent.java:5210) at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1579) at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1502) at javax.swing.RepaintManager.paint(RepaintManager.java:1272) at javax.swing.JComponent._paintImmediately(JComponent.java:5158) at javax.swing.JComponent.paintImmediately(JComponent.java:4969) at javax.swing.RepaintManager$4.run(RepaintManager.java:831) at javax.swing.RepaintManager$4.run(RepaintManager.java:814) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80) at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:814) at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:789) at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:738) at javax.swing.RepaintManager.access$1200(RepaintManager.java:64) at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1732) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756) at java.awt.EventQueue.access$500(EventQueue.java:97) at java.awt.EventQueue$3.run(EventQueue.java:709) at java.awt.EventQueue$3.run(EventQueue.java:703) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80) at java.awt.EventQueue.dispatchEvent(EventQueue.java:726) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

[virtuald]

I'm happy to accept a fix for this, but I don't personally have the time to do it myself.