Graham,
If you map the CCs in your RadioButtonsExample document, you can greatly simplify the coding:
Private Sub Document_ContentControlBeforeStoreUpdate(ByVal ContentControl As ContentControl, Content As String)
Dim oXMLPart As CustomXMLPart
Dim oNode As CustomXMLNode
Set oXMLPart = ContentControl.XMLMapping.CustomXMLPart
If Content = True Then
For Each oNode In oXMLPart.DocumentElement.ChildNodes
'The first character of the title and node name identifies the set (i.e., "A" or "B")
If Left(oNode.BaseName, 1) = Left(ContentControl.Title, 1) Then
If Not oNode.BaseName = ContentControl.Title Then
oNode.Text = "false"
End If
End If
Next
End If
lbl_Exit:
Exit Sub
End Sub