Hello Grzegorz,
1) Fixed Navigation is fairly simple to add to Versla, just add the following to your custom SCSS file:
@media (min-width: 768px) {
#g-navigation {
position: fixed;
z-index: 10000;
width: 100%;
}
#g-slideshow {
margin-top: 100px;
}
}
2) Could you elaborate more on "Group children menu"?
3) You can add this also to your custom SCSS file for mobile menu to slide from top:
#g-page-surround {transform: none !important;}
body #g-offcanvas {position: relative;width: 100%;}
4) We provide a Popup Module in the Particles section.
5) It is possibility down the road:
www.rockettheme.com/blog/team/218-rocket...n#comment-2686701915