Update: I had discovered that this original ADMX template were missing some Internet Explore 11 Group Policy settings. As a result the ADMX/ADML pack has now been re-released but can be downloaded using the same link below.
Microsoft has just released the Administrative Templates (ADMX/ADML) files that allow you to configure their newest Group Policy Administrative Template setting for Windows 8.1 Update and Windows Server 2012 R2 Update. These files are already provided with the operating system when you go to install it however this download allows you to update the policy settings even on an older version of the OS.
The changes to these files mainly include the support for the new group policy setting regarding the new UI setting for configuring the start screen and task bar.
The best way to deploy these files is to simply copy them to the Group Policy Central Store. This will update all your group policy objects in one easy step. Even if you are not running the latest OS in you environment there is no issues with updating the ADMX/ADML files as all the setting are fully backwards compatible and will just mean one less step to do when you do upgrade in the future.
Download the Windows 8.1 update ADMX/ADLM pack from http://www.microsoft.com/en-us/download/details.aspx?id=43413