OSConfig will create a Registry Snapshot CMD file at C:\Windows\OSConfig\Registry\_Snapshot.cmd
Run this file (as Administrator) and it will create new Registry exports. It will have a pause midway through the script allowing you to make changes to your OS
Once you have made changes to you OS, press any key to continue the _Snapshot.cmd script. This will create new Registry exports.
You can easily use Notepad++ (with Compare plugin) to find changes that you need to make REG files for use in OSConfig.