Hi Ben,

1. Both sets of web parts get added, but the ones in the requiredWebParts list can't be removed from the portal page. The ones from preferredWebParts can.

2. Correct.

3. The behavior comes from the "Workbook Description" web part. It's never advertised in the drop downs in the UI, but you should be able to add it to your list of web parts in your XML file. Given its UI, it's probably best if it's first in the list.

Thanks,
Josh