Hi Graham,

You can try to customize the following file that are responsible for email output here, /components/com_easysocial/themes/wireframe/emails/html/registration/login.php and add the link to download your file.

By the way this request will fall under "customizations" request and I am really sorry but unfortunately we cannot accommodate your request currently as it is beyond our support scope's policy as outlined in http://stackideas.com/support .

Having said that, if you require us to perform the customization for you, you can always request for a quote from us at https://crm.stackideas.com and select "Customizations" . Our sales person would be glad to send you a quote for the customizations that you have requested. Thanks for understanding.