Hi Kevin,
Thank you for posting in the Microsoft Community Forums.
If you, as a domain administrator, are still unable to change the personalization settings for the lock screen interface and receive the message “Some of these settings are managed by your organization”, it is likely that your Group Policy has configured settings that override the user's personalization choices.
Are you trying to block these related Group Policy settings?
To resolve this issue, you can navigate to “Computer Configuration” (or “User Configuration”) > “Administrative Templates” > “Control Panel “ > ‘Personalization’.
Regarding filtering out local PC registry settings, I don't really understand what you want to require.
Maybe your needs don't have much to do with AD (Active Directory), you can try to ask under other tags about how to filter out local PC registry settings.
Best regards
Neuvi Jiang