Pop up! plugin, box never shows

Hi, I have already installed this plugin in the past, but it
never worked for me. Maybe is a plugins-conflict, I don't know...

My site: http://www.DOTforexPLUSerDOT.it
(just copy the name above and cancel the text in capital letters)

Plugin list:

Akismet
BuddyPress
Contact Form 7
Exec-PHP
FeedBurner FeedSmith
GoCodes
Popover plugin
Related Posts Thumbnails
s2Member
SI CAPTCHA Anti-Spam
Special Text Boxes
Subscribe To Comments
WordPress SEO
WP-Optimize
WP Minify
WP Super Cache
WP Super Edit