Users to register before downloading

I need users to register before downloading sermons, so we know who they are and can include newsletter options in the form as well. Somehow I cannot get such security setting going under Joomla 3.4 under Global settings ?

There are multiple places where you can restrict access.
In the SermonSpeaker options, in the "Detailpage" tab you can set the "Detailpage Access Level". This will restrict access to any sermon detailpage.
You can also use the access level in the categories to restrict access to all sermons, series and speakers in that category.

However there is no access check to the files itself. So if a visitor knows the filename, he will be able to download it.