I extracted it in such a way that the folder structure is preserved, meaning that it extracted with all the folders, and the file is at the end. I only removed the read-only attribute, but Paint still won't open it.
Forget about Paint.Net - if you have Adobe Photoshop 5.0 or higher, install the plugin from nVidia - the link is above, and you'll be happy!

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Неудачное планирование ведёт к неудаче ...
NCF - мод, добавляющий дополнительных существ в HeroesV 3.1