Everything seems to work fine but is it?

I keep getting the following error in the console when loading a particular world.

Attached is the program

Alice version: 2.2 02/10/2011



PropertyReference[property=edu.cmu.cs.stage3.alice.core.property.Ove rridableElementProperty[name=element,owner=edu.cmu.cs.stage3.alice.core.re sponse.PropertyAnimation[world.clearBoard.__Unnamed2__.__Unnamed4__.__Unnam ed1__.__Unnamed1__.__Unnamed1__]],criterion=edu.cmu.cs.stage3.alice.core.criterion. InternalReferenceKeyedCriterion[clearBoard.__Unnamed2__.__Unnamed4__.__Unnamed1__. __Unnamed1__.__Unnamed1__.__Unnamed0__]]

java.lang.NullPointerException

at edu.cmu.cs.stage3.alice.core.question.array.ArrayO bjectQuestion.getValueClass(ArrayObjectQuestion.ja va:34)

at edu.cmu.cs.stage3.alice.core.response.PropertyAnim ation.updateOverrideValueClasses(PropertyAnimation .java:52)

at edu.cmu.cs.stage3.alice.core.response.PropertyAnim ation.propertyChanged(PropertyAnimation.java:67)

at edu.cmu.cs.stage3.alice.core.Element.propertyChang ed(Element.java:265)

at edu.cmu.cs.stage3.alice.core.Property.onChanged(Pr operty.java:423)

at edu.cmu.cs.stage3.alice.core.Property.onSet(Proper ty.java:438)

at edu.cmu.cs.stage3.alice.core.Property.set(Property .java:455)

at edu.cmu.cs.stage3.alice.core.reference.PropertyRef erence.resolve(PropertyReference.java:52)

at edu.cmu.cs.stage3.alice.core.Element.load(Element. java:1532)

at edu.cmu.cs.stage3.alice.authoringtool.dialog.LoadE lementProgressPane.construct(LoadElementProgressPa ne.java:37)

at edu.cmu.cs.stage3.progress.ProgressPane$2.run(Prog ressPane.java:84)

at java.lang.Thread.run(Unknown Source)