I don't see a way to change all the icons wholesale to match the icons in the screenshot for the theme.
You'd need to be using the exact same programs and everything in order to even load the authors "theme". Not very likely. Authors can incude their themes, which would include the icons they are using, but in order to do a one click change to match the screenshot, like I said, you'd have to have the programs that were on the SS dock on your dock.