There needs to be an audit log of the list of emails that get sent out. Please take a look at the Warning for registering and Mailchimp Integration UI feature requests. I did not know that registering a user manually would cause it to trigger an email because there was no notice or warning. I wasn't sure if it did so I wanted to check an audit log but there was none to see if anything was sent out. Definitely need an audit log if there going to be any communication coming out of Big Marker.