Thank you very much master.
Now I have another problem. I have 20 groups with 10 images inside. I have put all the photos at the bottom to be able to do a crossface between the groups.
If I do it manually it does the crossfade correctly but I want to give each group a duration of 20 seconds. if I set an autofollow, after 20 seconds it fires the next group but it doesn't crossfade. How can I solve it or in what way should I do it? Thank you so much