I have prepared a project, extracting RadDataForm's templates and resources. It is attached for your reference. In order to customize the way in which DataFormDataFields' labels are measured you should modify PART_DataFormDataFieldGrid. Please, do not hesitate to contact us immediately if any further inquires occur.
All the best,
the Telerik team
Register for the Q2 2011 What's New Webinar Week. Mark your calendar for the week starting July 18th and book your seat for a walk through of all the exciting stuff we will ship with the new release!