Modal box use to show, not anymore

Hi,

really like how the plugin works, but for some reason, sometimes see the modal and other times not. I was thinking it had something to do with the cookies, but i hit the delete cookies button and nothing changes, are there instructions on how to set all the proper cookie info?

the website is at http://apartmentbrowse.com

any guidance would be great!, thanks for the help

http://wordpress.org/plugins/modal-dialog/