How do i capture a folder of registry keys and make then a exe batch?

I'm modifying an old game.. including patches, and modifications. I want to make my own installer using WinRar but WinRar doesn't do registry keys. I thought I'd make a self executing batch file with all my needed registry keys and point WinRar to that during install. I heard this was possible but have no idea how to do it.

Of course the folder that all the keys in it has sub folders with more registry keys.. I'd like to be able to capture them all and maintain that directory structure. Is this possible with a self executing batch file.. if so, How do I do it?

I don't need anyone to tell me what to do in WinRar once i have the file.. I know that already. I just need to know how to make that batch file itself. I can do it by exporting it to a .reg file, but that's no good.. i need an exe that WinRar can execute plus I need it to install these keys silently - otherwise I get the popup asking if I'm sure I want to install these keys. Since this version of the game will be shared with friends, I don't need that, I need it to look professional.

Thank you.