This is ALL you need do to make your SSL operative. If it is not operating when it OUGHT to, then you have malconfigurations in your template. (Assuming your server is set up for SSL to operate under the same domain and domain path).
// Define the webserver and path parameters
// HTTP_SERVER is your Main webserver: eg-http://www.yourdomain.com
// HTTPS_SERVER is your Secure webserver: eg-https://www.yourdomain.com
// Use secure webserver for checkout procedure?
The way to test this is to switch your template to the "classic" template, and see of the desired behaviour occurs. If it does, your custom template is faulty.