Updating My Customized Integrated Template files from version 5.1.2 to version 5.2.3

As I've been going through learning WHMCS and utilizing it somewhat successfully to my advantage, I've realized I've missed out on a huge area that I was not aware of. I ordered my integrate template service from WHMCS on 12/31/11 and at the time I would have version 5.1.2 of WHMCS, so that is how I determined my template files go that far back. However, looking at the release logs does not tell me the detailed code changes as the newer release notes do.

What is the best way of finding out all the updates I am missing and being as up to date as possible with a integrated template? Furthermore, is there a way I can pay to have my template files updated?

Here is what I mean:

Version 5.1.2 Release Notes

http://docs.whmcs.com/Version_5.1_Release_Notes#Template_Changes

The following template changes have been made to system templates:

3dsecure.tpl - New method of form submission - not a required update

affiliates.tpl - Removed billing cycle column

clientareacreditcard.tpl - Added preserving of card type/expiry date selections on validation failure

Version 5.2.3 Release Notes

/default/

affiliates.tpl

* Line 89 - Change of colspan from 6 to 5

bulkdomainchecker.tpl

bulkdomaintransfer.tpl

* Line 48 - Class change on table

clientareachangesq.tpl

* Removed File. Replaced with new functionality.

Use Winmerge if you're on a Windows machine to compare the new templates against your version and merge the changes in...