Run Ensemble and select the Graphics3d->Cube demo. If you mouse over the Source code tab you will get the following exception repeatedly and the animation will stop:

java.lang.ClassCastException: com.sun.javafx.geom.BoxBounds cannot be cast to com.sun.javafx.geom.RectBounds
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:817)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.sg.BaseNode.accumulateGroupDirtyRegion(BaseNode.java:852)
at com.sun.javafx.sg.BaseNode.accumulateDirtyRegions(BaseNode.java:694)
at com.sun.javafx.tk.quantum.PaintRunnable.setDirtyRect(PaintRunnable.java:98)
at com.sun.javafx.tk.quantum.PaintRunnable.paintImpl(PaintRunnable.java:118)
at com.sun.javafx.tk.quantum.PaintRunnable.run(PaintRunnable.java:236)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRunAndReset(FutureTask.java:317)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:150)
at com.sun.prism.render.RenderJob.run(RenderJob.java:29)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at com.sun.javafx.tk.quantum.QuantumRenderer$ObservedRunnable.run(QuantumRenderer.java:70)
at java.lang.Thread.run(Thread.java:662)