Let me try using this gadget 'link' on the tool bar on top of the 'text input box', I did a select and copy of this Technology in Action Complete (12th Global Ed)(gnv64).pdf and now reselect the file name in the text input box and click on the 3-link chain symbol and select 'Insert link'. Then I copy and paste the Dropbox url where that file lives into the url input field and voila I get to see the file name in blue and when I right click it I see option to 'save link as' (in Firefox terminology meaning 'download') and I left click it I see the Dropbox url.

May be this is easier for you than sending emails. ;-)