Not really an answer to your question but...

Do you have the frame rate visible in CS while playing? When playing games through Steam I have my FPS display at all times. It's a pretty handy feature. 

After enabling the FPS counter try playing CS with and without Deskscapes to see if there is an impact. See below to enable the FPS counter. 

Hello, I have exactly the same question. I have an animated wallpaper in the wallpaper engine, every time I do not disable the wallpaper, my fps drops slightly in games, do you know how I can fix it? I just don't understand what's wrong.