Xpages - Unhandled event loop exception

Question

As title says, trying to use the script editor behind a button on a custom control throws Unhandled event loop exception in plug-in org.eclipse.ui

Domino Designer 10.0.1FP5 Revision 20200505.1852-FP5

Any ideas' what's causing this and/or how to resolve?

Thanks

java.lang.NullPointerException
    at com.ibm.designer.domino.scripting.JSFScriptContent.getJSFExpression(Unknown Source)
    at com.ibm.designer.domino.scripting.JSFScriptContent.getExpression(Unknown Source)
    at com.ibm.designer.domino.scripting.internal.ScriptingDialogUICompositor.addComputedValueRadios(Unknown Source)
    at com.ibm.designer.domino.scripting.internal.ScriptingDialogUICompositor.createScriptingPaneControl(Unknown Source)
    at com.ibm.designer.domino.scripting.internal.ScriptingForm.createRightContents(Unknown Source)
    at com.ibm.designer.domino.scripting.internal.ScriptingForm.createContents(Unknown Source)
    at com.ibm.designer.domino.scripting.dialog.ScriptDialog.fillClientArea(Unknown Source)
    at com.ibm.commons.swt.data.dialog.LWPDCommonDialog.createDialogArea(Unknown Source)
    at com.ibm.commons.swt.data.dialog.LWPDCommonDialog.createContents(Unknown Source)
    at com.ibm.designer.domino.scripting.dialog.ScriptDialog.createContents(Unknown Source)
    at org.eclipse.jface.window.Window.create(Unknown Source)
    at org.eclipse.jface.dialogs.Dialog.create(Unknown Source)
    at com.ibm.designer.domino.scripting.dialog.ScriptDialog.create(Unknown Source)
    at org.eclipse.jface.window.Window.open(Unknown Source)
    at com.ibm.commons.swt.data.dialog.LWPDCommonDialog.open(Unknown Source)
    at com.ibm.designer.domino.xsp.internal.editors.MethodBindingEditor.callDialog(Unknown Source)
    at com.ibm.commons.swt.data.editors.api.CompositeEditor.callDialog(Unknown Source)
    at com.ibm.commons.swt.data.editors.support.DialogButton.onClick(Unknown Source)
    at com.ibm.commons.swt.data.editors.support.DialogButton.handleEvent(Unknown Source)
    at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
    at org.eclipse.swt.widgets.Display.sendEvent(Unknown Source)
    at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
    at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(Unknown Source)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Unknown Source)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(Unknown Source)
    at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(Unknown Source)
    at org.eclipse.ui.internal.Workbench$5.run(Unknown Source)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Unknown Source)
    at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Unknown Source)
    at org.eclipse.ui.PlatformUI.createAndRunWorkbench(Unknown Source)
    at com.ibm.rcp.personality.framework.internal.RCPApplication.run(Unknown Source)
    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.internal.app.EclipseAppContainer.callMethodWithException(Unknown Source)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(Unknown Source)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(Unknown Source)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(Unknown Source)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(Unknown Source)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(Unknown Source)
    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(Unknown Source)
    at org.eclipse.equinox.launcher.Main.basicRun(Unknown Source)
    at org.eclipse.equinox.launcher.Main.run(Unknown Source)
    at com.ibm.rcp.core.internal.launcher.Main.startLaunch(Unknown Source)
    at com.ibm.rcp.core.internal.launcher.Main.main(Unknown Source)
    at com.ibm.rcp.core.internal.launcher.Main.run(Unknown Source)

Session Data:

eclipse.buildId=20200505-1305

java.fullversion=8.0.6.5 - pwi3280sr6fp5-20200111_02(SR6 FP5)

JRE 1.8.0 Windows 8 x86-32-Bit 20200108_436782 (JIT enabled, AOT enabled) OpenJ9 - 7d1059c

OMR - d059105

IBM - c8aee39

BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en

UPDATE:

Plug-in at 'C:\Users\chririchards\Applications\Notes\Data\workspace\SERVERNAMEHIDDEN_2fUK_2fDTT\devis_5ccr_5cxpages_5cindconf.nsf' does not have an OSGi bundle manifest. To use a 2.0 style plug-in you must install the plug-in converter service. Go to Help > Install New Software and install 'Eclipse 2.0 Style Plugin Support' from 'The Eclipse Project Updates' software site.