Most of the time the normal version doesn't have a image folder. You need to do this to extract the images.
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Copy and paste the depack.rpy file in the "game" folder and run the game. After a while (depending on pc speed) a folder called "unpacked" will appear and start filling up with all the art extracted, wait till the game has loaded after that you can close the game. The depack.rpy file will work on any game made with Ren'py so save it and use it when you want some images of a Ren'py game.
Don't know if this works on a compressed version.
EDIT attached depack.rpy