[Soyweiser]

I'm getting this error:

org.eclipse.emf.common.util.BasicEList$BasicIndexOutOfBoundsException: index=0, size=0
	at org.eclipse.emf.common.util.BasicEList.get(BasicEList.java:352)
	at org.larz.dom3.editor.DmEditor$1$2.process(DmEditor.java:144)
	at org.larz.dom3.editor.DmEditor$1$2.process(DmEditor.java:1)
	at org.eclipse.xtext.util.concurrent.IUnitOfWork$Void.exec(IUnitOfWork.java:36)
	at org.eclipse.xtext.util.concurrent.IStateAccess$AbstractImpl.readOnly(IStateAccess.java:40)
	at org.eclipse.xtext.ui.editor.model.XtextDocument.readOnly(XtextDocument.java:70)
	at org.larz.dom3.editor.DmEditor$1.run(DmEditor.java:141)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.larz.dom3.editor.DmEditor.addPages(DmEditor.java:104)
	at org.eclipse.ui.forms.editor.FormEditor.createPages(FormEditor.java:138)
	at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:348)
	at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:670)
	at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:465)
	at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595)
	at org.eclipse.ui.internal.PartPane.setVisible(PartPane.java:313)
	at org.eclipse.ui.internal.presentations.PresentablePart.setVisible(PresentablePart.java:180)
	at org.eclipse.ui.internal.presentations.util.PresentablePartFolder.select(PresentablePartFolder.java:270)
	at org.eclipse.ui.internal.presentations.util.LeftToRightTabOrder.select(LeftToRightTabOrder.java:65)
	at org.eclipse.ui.internal.presentations.util.TabbedStackPresentation.selectPart(TabbedStackPresentation.java:473)
	at org.eclipse.ui.internal.PartStack.refreshPresentationSelection(PartStack.java:1254)
	at org.eclipse.ui.internal.PartStack.setSelection(PartStack.java:1207)
	at org.eclipse.ui.internal.PartStack.showPart(PartStack.java:1606)
	at org.eclipse.ui.internal.PartStack.add(PartStack.java:497)
	at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:103)
	at org.eclipse.ui.internal.PartStack.add(PartStack.java:483)
	at org.eclipse.ui.internal.EditorStack.add(EditorStack.java:112)
	at org.eclipse.ui.internal.EditorSashContainer.addEditor(EditorSashContainer.java:63)
	at org.eclipse.ui.internal.EditorAreaHelper.addToLayout(EditorAreaHelper.java:225)
	at org.eclipse.ui.internal.EditorAreaHelper.addEditor(EditorAreaHelper.java:213)
	at org.eclipse.ui.internal.EditorManager.createEditorTab(EditorManager.java:778)
	at org.eclipse.ui.internal.EditorManager.openEditorFromDescriptor(EditorManager.java:677)
	at org.eclipse.ui.internal.EditorManager.openEditor(EditorManager.java:638)
	at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2860)
	at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2768)
	at org.eclipse.ui.internal.WorkbenchPage.access$11(WorkbenchPage.java:2760)
	at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:2711)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2707)
	at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2691)
	at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2674)
	at org.larz.dom3.ApplicationActionBarAdvisor$2$1.run(ApplicationActionBarAdvisor.java:153)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70)
	at org.larz.dom3.ApplicationActionBarAdvisor$2.run(ApplicationActionBarAdvisor.java:132)
	at org.eclipse.jface.action.Action.runWithEvent(Action.java:498)
	at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:584)
	at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:501)
	at org.eclipse.jface.action.ActionContributionItem$5.handleEvent(ActionContributionItem.java:411)
	at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
	at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053)
	at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4066)
	at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3657)
	at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2640)
	at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2604)
	at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2438)
	at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:671)
	at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
	at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:664)
	at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
	at org.larz.dom3.Application.start(Application.java:35)
	at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
	at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:369)
	at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:619)
	at org.eclipse.equinox.launcher.Main.basicRun(Main.java:574)
	at org.eclipse.equinox.launcher.Main.run(Main.java:1407)

When I try to open mytheology3_9.dm