ava.lang.NullPointerException
	at org.netbeans.spi.looks.Look.removeLookListener(Look.java:562)
	at org.netbeans.spi.looks.ProxyLook.removeLookListener(ProxyLook.java:1166)
	at org.netbeans.spi.looks.AccessorImpl.removeLookListener(AccessorImpl.java:36)
	at org.netbeans.api.nodes2looks.LookNode$FirerImpl.run(LookNode.java:842)
	at org.openide.util.Utilities$ActiveQueue.run(Utilities.java:2474)
[catch] at java.lang.Thread.run(Thread.java:534)