I had similar issue with one of the books I bought which had very lousy formatting
When I go on Manage my Kindle page it gives me option to download it and if I go for deliver to my PW I get the following message
We're sorry, this title is not currently available for download.
We are investigating the difficulty with this title and ask that you try again in 24 hours. If after that time you are still unable to access this title, please contact us for further assistance. We apologize for the inconvenience.
Thank you for shopping at Amazon.com!
But if I chose delivery to my Kindle 3 it does get the delivered and its same old lousy formatting.
Also, the book is not available for purchase in kindle format any more, I guess too many people complained, so I don't know what was the issue with your dictionary.