Plugin wiring

Hi there,

I'm making my way through "How to build Extensions" from Sebastian and have encountered some strange behaviour.

I can build and deploy the operators provided, but if I use either of the example "super" operators I cannot manually wire up the input of the inner operators, no yellow connecting line appears on mouse drag. However, the meta data is being passed though, and "autowire" connects everything as expected.

If I run Vega via Eclipse I can tag the following glitch message....

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at com.rapidminer.gui.flow.ProcessRenderer$9.mouseDragged(ProcessRenderer.java:1883)
	at java.awt.AWTEventMulticaster.mouseDragged(Unknown Source)
	at java.awt.Component.processMouseMotionEvent(Unknown Source)
	at javax.swing.JComponent.processMouseMotionEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

Can anyone suggest a way round this?