// JavaScript Document
window.addEvent('domready', function() {
//code below
var one = $('rotate1');//element with lower z-index
var two = $('rotate2');//element with higher z-index
var myImages = ['url(images/rotate1.jpg)', 'url(images/rotate3.jpg)','url(images/rotate4.jpg)','url(images/rotate5.jpg)','url(images/rotate6.jpg)'];
var i = $random(0, myImages.length-1);
//set first image
one.setStyle('background-image', myImages[0]);//or set to number that corresponds with 'the chosen' slide    
two.setStyle('opacity', 0);
var show = function() {
 i = $random(0, myImages.length-1);
 two.setStyle('opacity',0);
 two.setStyle('background-image', myImages[i]);
 two.set('tween',{duration: 2600});
 two.tween('opacity', [0,1]);
 (function(){one.setStyle('background-image', myImages[i]);i++;}).delay(5900)
}
show.periodical(6100);
//code above
});