Hello,
I’ve found a solution and you can try if it works for you too.
You need to change email-before-download.php which is located in /wp-content/plugins/email-before-download directory.
Look for:
$contact_form = do_shortcode("[contact-form-7 id=\"$contact_form_id\" \"$title\"]");
and change it to:
$contact_form = do_shortcode("[contact-form $contact_form_id \"$title\"]");
Hope that helps you.