I don’t have this problem more because I made this change to the code of inc/hooks/homepage-slider.php (ver. 1.0.3)

BEFORE: I use main slideshow setted up to show 3 posts

On line 64:

'orderby' => 'date' //EDITED,
'order'   => 'DES' //ADDED,
'cat' => $emag_feature_slider_category,
'offset' => 0 //EDITED

On line 136:

'orderby' => 'date', //EDITED
'order'   => 'DES', //ADDED
'offset' => 3, //ADDED

Now posts are inserted in the slideshow ordered by date and the first three appers in the slideshow and the 4th and the 5th appear on the side.

Thank you for the help, waiting for the next update 🙂