Turn on/off the Next and Back buttons on the skin

You can disable the back and next using the following JavaScript.  On slides where you want the buttons to be disabled, set the slide title(s) to "disable". Execute this JS on slide enter of the first slide in the project.

if ( window.cpInfoLastVisitedSlide === 1 )
{
window.cpAPIEventEmitter.addEventListener( 'CPAPI_SLIDEENTER', enterSlide, false );
}

function enterSlide( e )
{
var bck = document.getElementById( 'Backward' );
var fwd = document.getElementById( 'Forward' );

if ( e.Data.lb === "disable" )
{
bck.style.opacity = .5;
bck.style.cursor = 'default';
bck.style.pointerEvents = "none";

fwd.style.opacity = .5;
fwd.style.cursor = 'default';
fwd.style.pointerEvents = "none";
}
else
{
bck.style.opacity = 1;
bck.style.cursor = 'pointer';
bck.style.pointerEvents = "auto";

fwd.style.opacity = 1;
fwd.style.cursor = 'pointer';
fwd.style.pointerEvents = "auto";
}
}

You can only turn them off for all slides, not for individual slides, using Project, Skin Editor. You need custom Next/Back buttons, but you can put them on the first slide timed for the rest of the project. That will allow to hide them with the On Enter event when you don't want them.