Cannot view report layout under Helios(Eclipse 3.6)

After upgrade to Helios (Eclipse 3.6), I connected to Crystal Reports for Eclipse's update site (http://downloads.businessobjects.com/akdlm/crystalreportsforeclipse/2_0/update_site/), and installed the latest cr4e.2.0.7.

But opening a report file, there is only "Expressions" page editor being displayed. Other page such as "Layout" or "Preview" are just disappeared.

In my Helios IDE, there are modules installed as below:

GEF                   3.6.0.v20100519-2050-7G7R-A5WNc7QL_fXBGjRZPUUiKPJ
EMF                   2.6.0.v20100614-1136
WDT                   3.2.0.v201005241510-7O7CFb3EMf84nP-FHuc10NTz--M3
XSD                   2.6.0.v20100614-1136
Oracle Database Tool  1.6.0.201007221419

Here is what CR4E complained in error logs, it seems that IEditorInput param was passed a value of null.

java.lang.IllegalArgumentException:      at org.eclipse.core.runtime.Assert.isLegal(Assert.java:63)     at org.eclipse.core.runtime.Assert.isLegal(Assert.java:47)     at org.eclipse.ui.part.EditorPart.setInput(EditorPart.java:224)     at org.eclipse.gef.ui.parts.GraphicalEditor.init(GraphicalEditor.java:346)     at org.eclipse.ui.part.MultiPageEditorPart.addPage(MultiPageEditorPart.java:237)     at com.businessobjects.crystalreports.rcputilities.NiceMultiPageEditor.addPage(NiceMultiPageEditor.java:77)     at org.eclipse.ui.part.MultiPageEditorPart.addPage(MultiPageEditorPart.java:211)     at com.businessobjects.crystalreports.designer.uibase.editor.CrystalReportsEditor.addPage(CrystalReportsEditor.java:292)     at com.businessobjects.crystalreports.designer.uibase.editor.ReportEditorExtensionManager.loadPagesFromExtensionRegistry(ReportEditorExtensionManager.java:98)     at com.businessobjects.crystalreports.designer.uibase.editor.CrystalReportsEditor$DocumentLoadingRunnable.attachDocumentAndPages(CrystalReportsEditor.java:645)     at com.businessobjects.crystalreports.designer.uibase.editor.CrystalReportsEditor$DocumentLoadingRunnable.access$1000(CrystalReportsEditor.java:507)     at com.businessobjects.crystalreports.designer.uibase.editor.CrystalReportsEditor$DocumentLoadingRunnable$1.run(CrystalReportsEditor.java:618)     at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)     at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:134)     at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4041)        ... ...

Please take a look at the problem, and give a solution for Helios users.

Thank you.