Hi i have have no idea about actionscript but this javascript will do the same thing.
<script language="JavaScript">
function random_image(){
var myimages=new Array()
myimages[1]="./path/Img_0568.jpg"
myimages[2]="./path/Img_0570.jpg"
myimages[3]="./path/Img_0571.jpg"
myimages[4]="./path/Img_0572.JPG"
var ry=Math.floor(Math.random()*myimages.length)
if (ry==0)
ry=1
document.write('<img src="'+myimages[ry]+'" border=0>')
}
random_image()
//-->
</script>
rob