I too struggled to get a working exit button and had one working until I started using the multiscreen.html ( Captivate 6 ) so that users are directed to html5 if their browsers support it. Unfortunatly the multiscreen.html code does not open a child window that would allow my close button to work and I was not able to find any posts that resolved this (let me know if you have a solution).
My solution was to use a fancybox that has an exit button on it to display the captivate project (works great for all browsers, project recorded in 995 x 627):
<script type="text/javascript">
$(document).ready(function () {
$("#btn_acceder").click(function () {
//window.open(/url/multiscreen.html');
$.fancybox({
//'orig' : $(this),
'type' : 'iframe',
'href': '/url/multiscreen.html',
'width' : 1020,
'height' : 700,
'autoScale' :false,
'enableEscapeButton' : true,
'transitionIn' : 'none',
'transitionOut' : 'none'
});
return(false);
});
});</script>
<div style="text-align: center;"><span class="mt30"></span><br />
<button class="btn_classique" id="btn_acceder"><span class="g"></span><span class="m">button text</span><span class="d"></span></button> </div>