plone/plone.formwidget.namedfile — pull request #1 by lentinj (2012-10-08 17:58:25+00:00)
Title: Use the download_url function in display templates too 

This seems slightly too obvious, I'm somewhat afraid.

However, it seems to help my case when the context is a Dict. (I'm also being naughty and overriding download_url, but that's another matter.)