How do I customize the folders' icons in "This PC"

Hello, I've being trying to change the icons in the folders from "This PC". I know how to change icons (Properties -> Customize), but the icons don't show on "This PC". Example: I change the icon for the Downloads folder on C:\Users\MyName\Downloads, but the Downloads folder on "This PC" remains the same.

How can I change it? I stumbled across a program how does it, but I'm writing my own program as part of this huge Class Library (DLL) I'm making to present as a part of my thesis and I don't know what should I change on the registry to pull it off. So, what should I change on the registry to customize the folder icons on "This PC"?
Thank you.