Right now, when a books is finished being generated/rendered, it gives you a bunch of text with a bunch of links in it. One of those text links is the 'Download the file' link, but it is virtually lost in the text.

Instead it should show you a giant green "Download Now!" button, similar to the example here:
http://www.android.com/filetransfer/

You could easily use our jQuery.ui library to make such a button. See the example at Wikidata here:
https://www.wikidata.org/wiki/Wikidata:Project_chat

Version: unspecified
Severity: normal
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=37448