When running the attached app or jar, press "right" then "enter" and you will get:
java.lang.NullPointerException
at com.sun.javafx.sg.BaseCacheFilter.imageDataUnref(BaseCacheFilter.java:429)
at com.sun.javafx.sg.prism.NGNode$CacheFilter.imageDataUnref(NGNode.java:885)
at com.sun.javafx.sg.BaseCacheFilter.invalidate(BaseCacheFilter.java:420)
at com.sun.javafx.sg.BaseNode.invalidateCache(BaseNode.java:830)
at com.sun.javafx.sg.BaseNode.markTreeDirty(BaseNode.java:763)
at com.sun.javafx.sg.BaseNode.markDirty(BaseNode.java:703)
at com.sun.javafx.sg.BaseNode.setTransformMatrix(BaseNode.java:344)
at javafx.scene.Node.impl_updatePG(Node.java:531)
at javafx.scene.Parent.impl_updatePG(Parent.java:105)
at javafx.scene.layout.Region.impl_updatePG(Region.java:1981)
at javafx.scene.Node.impl_syncPGNode(Node.java:476)
at javafx.scene.Scene$ScenePulseListener.synchronizeSceneNodes(Scene.java:2222)
at javafx.scene.Scene$ScenePulseListener.pulse(Scene.java:2341)
at com.sun.javafx.tk.Toolkit.firePulse(Toolkit.java:358)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:560)
at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:540)
at com.sun.javafx.tk.quantum.QuantumToolkit$15.run(QuantumToolkit.java:425)
at com.sun.glass.ui.lens.LensApplication$RunnableEvent.dispatch(LensApplication.java:167)
at com.sun.glass.ui.lens.LensApplication._runLoop(LensApplication.java:745)
at com.sun.glass.ui.lens.LensApplication.access$600(LensApplication.java:55)
at com.sun.glass.ui.lens.LensApplication$4.run(LensApplication.java:804)
at java.lang.Thread.run(Thread.java:722)

this only happens on Pi works fine on desktop