The source of the problem often lies in the fact, that users don’t fill in the Document types property, which means that system uses the View_Tree_Joined view (where the custom fields are not included) instead of a particular view based on the CMS.MenuItem document type. Although our listing webparts are designed to list CMS.MenuItems when this property is not defined, you need to populate the Document types property to be able to display document type specific field values.
In short, entering the CMS.MenuItem value into the Document types property does the trick and should allow your custom fields to be shown properly.
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