mailchimp popup form not showing up
It might be that you yourself are already subscribed. Here's JS that can delete the cookie that marks that:
document.cookie = "MCPopupClosed=; expires=Thu, 01 Jan 1970 00:00:00 UTC; path=/";document.cookie = "MCPopupSubscribed=; expires=Thu, 01 Jan 1970 00:00:00 UTC; path=/";
Your issue is probably that the correct jquery version is not being called. I believe you need a minimum of 1.4.4 and you may find if you have a look at the link below it is a problem with how the pop up is looking for the jquery.js file:
https://www.organicweb.com.au/19561/wordpress/mailchimp-popup-instructions/
I believe mailchimp uses cookies to display the popup only once, so once you see it once on your site, it won't display again unless you delete your cookies. Not sure if there is a setting to change this or not.