Ok, since I really, really, hate to admit defeat (specially at the hands of Microsoft) I armed myself with a copy of Registry Monitor and spent some time sniffing what Explorer was doing in the Windows Registry while displaying the Recently Used Documents list.
And so I figured it out. I can now make NextSTART Recent Document's menu and WorkShelf's Recent Documents shelf display exactly the same items as those displayed in the Windows Start Menu.
Hope that makes you a bit happier.
Anyway, since I also don't want to alienate those users who like the Recent Documents Menu/Shelf as they currently are, I think I will also add a choice in Preferences to select how many recent documents you want displayed. By default, that number will be the current Explorer default (usually 15).