Still don't see this issue.
But you avoid this behavior by changing function
myButton in js/main.js. Replace this functino by
function myButton (buttonText,buttonLink) {
document.write(' <DIV ID="flashMovie'+(anim_ids+1)+'" STYLE="width: 200; height: 31; z-index: 100;" onClick="showPage(\''+buttonLink+'\','+anim_ids+1+ ')">');
document.write('</DIV>');
}