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I tested this Winston and get the same results as you do. the {return} seems to work so I am leaning toward a bug. Can you substitute a fixed number of spaces instead of using the tab?
I would recommend dropping Tim a note at http://www.timothyarmes.com/contact.php and letting him know. Personally, I would never use a tab and am not sure why it would be included. But, if it works for you, (in this case doesn't ;-) great.
As far as missing data, I am not sure what Victoria meant. She might have thought the ? was generated from one of the other fields being empty. Just a guess. Good luck.