Any danger in copying latest ADMX (& lang files) into AD Central Store?
Solution 1:
No danger I can think off.
Some official reading:
New Windows Vista–based or Windows Server 2008–based policy settings can be managed only from Windows Vista–based or Windows Server 2008–based administrative machines running Group Policy Object Editor or Group Policy Management Console. Such policy settings are defined only in ADMX files and, as such, are not exposed on the Windows Server 2003, Windows® XP, or Windows 2000 versions of these tools. An Administrator will need to use the Group Policy Object Editor from a Windows Vista–based or Windows Server 2008–based administrative machine to configure a new Windows Vista–based Group Policy settings.
In Group Policy for versions of Windows earlier than Windows Vista, if you modify Administrative template policy settings on local computers, the Sysvol share on a domain controller within the domain is automatically updated with the new ADM files. In Group Policy for Windows Server 2008 and Windows Vista, if you modify Administrative template policy settings on local computers, Sysvol will not be automatically updated with the new ADMX or ADML files (ADML files are XML-based ADM files that contain language-specific settings). This change in behavior is implemented to reduce network load and disk storage requirements, and to prevent conflicts from occurring between ADMX files and ADML files when edits to Administrative template policy settings are made across different locales. To ensure that any local updates are reflected in Sysvol as well, you must manually copy the updated ADMX or ADML files from the PolicyDefinitions folder on the local computer to the Sysvol\PolicyDefinitions folder on the appropriate domain controller.
From https://technet.microsoft.com/en-us/library/cc709647(v=ws.10).aspx