Hi!
You can remove the menu by adding a bit of css in "Custom CSS for Mobile Version" field in "Lay Options" -> "Misc Options".
.navbar, nav{
display: none;
}
body{
padding-top: 0!important;
}
Hey, yeah that's right. You just need to create a page in "Pages" and then set it as the frontpage in the customizer.
The slideshow will come as an addon. Right now I'm working on an update for Lay Theme and then I will work on the slideshow addon.