BoltMail
How can I add custom fields to my newsletters or templates created outside of the application, eg. in Frontpage or Dreamweaver?
Simply copy the tags used in the application into your HTML file to add these custom fields.

So to begin, create a dummy newsletter in the application and click on the "Insert Custom Field" option. A new window will pop open with a list of the custom field options you can enter. Simply copy and paste the custom field you would like to use in your newsletter.

eg. %%UNSUBSCRIBE%%

Keep in mind however, that when you preview a newsletter, i.e. Send it to yourself using the preview option, the custom fields will not be parsed, because your preview email address does not contain the custom fields. In order for the custom fields, including unsubscribe to work, you must send the newsletter out to a contact list. If you'd like to test this, simply create a test contact list, add yourself as a contact and send the newsletter to that contact list.