I would be glad to help. To setup Showtime Anytime, you will first need to setup an account with Showtime. You can use your Xfinity account information when you register. From the Showtime Anytime site, click on Activate at the top right, and then choose Xfinity as your provider. You should be presented with a login screen asking for your Xfinity account information. This information should be written on your Xfinity manual that you received when your Xfinity service was set up. If you account name is ***** ***** try the account name with and without the @comcast.net part. Your Xfinitity account name may also be your primary email address, but it is probably a different account name ending in @comcast.net. Double-check your Xfinity documentation to be sure.
If you are unable to find this information, let me know and I can walk you through the steps to get this information via the Xfinity web-site.