It doesn't violate the EULA since this is only a program that you are installing and using. It's no different than say installing Stardock WindowBlinds to change the theme in Windows 7.
If it was a hack that tampered with the licensing or distribution of Windows 7, then it would violate the EULA.
To read the exact EULA for you editon of Windows 7, you can read this PDF file
Unfortunately, Oceanis doesn't have an official website from the publisher. It was allowed to be distributed (hosted) by us and other sites to share with the public instead. The shuffle timing is exactly the same times as if you were using the built-in Desktop Slideshow
feature in say Windows 7 Ultimate though.