I don't think you're gonna like this.
Page 2.
http://www.chesscafe.com/text/review730.pdf
You are right, I don't but it is all right, I think I should get CT-ART 3.0, thank you very much for your help, cheers.
It IS possible to sort by degree of difficulty !
In the bottom-right window, reduce "themes" and open "difficulty"
I'm not sure I was clear so here is the "tutorial" in picture :
Click inside the red circles
http://imageshack.us/photo/my-images/707/ctart41.jpg/
http://imageshack.us/photo/my-images/96/ctart42.jpg/
Hello dear chess lovers, please tell me how to sort exercises by the the degree of dificulty, I haven't been able to find this setting, thank you very much, cheers.