I have already done the custom function to prepoulate a custom field.  However the issue i have is that when i try and set up an automation rule it will only let me select the email or secondary email to send the template to.  It obviously doesnt recognise my custom field as an email address. 

Therefore is it possible to either: 

- add the custom field to the automation email list

- add a custom fucntion to the secondary email address so i can use this instead?  (this would be my preference as i dont us secondary email for anything at the moment) 

Thanks 

Martin