Thank you for your fast answers.
I made what you have to suggest. The first try(essay) put for a long time to reveal the pop-up. He(it) worked that only once.
On the other hand when I navigate my iPhone it works but not with Google chromium, Internet Explorer or Firefox on various computers.
Thank you for your answer.
The plugin is enabled. The caching is emptied and it does not still work. You confirm of what I thought:it appears no more.
I had tried several other plugins but they worked the first clicks and after anymore as yours (or they were not compatible with mailchimp)
I think that there is a problem with the theme. I repatriated my pages of a wordpress.com version for version .org, can it play?
Thanks