You can add files quickly to an email template now in ISN. First, go to Email - My Email Templates and click the pencil icon to edit the email template you want to add the file to.
Next, scroll down and edit the template. Place your cursor where you want the file's link to be and hit the upload button.
The file will upload and exist as a link right where you had your cursor.
If you have any questions about this process please let us know! You can reach us by chat, email at email@example.com, or phone at (800) 700-8112.