I've created a filter so I can add an email link per post rather than going in and editing the php. It's a simple function that just replaces '[email-link]' with the return of email_link() function.
Other than that, the plugin is the latest version. When I click on the email link, it gives me a 404. This is both for the popup and the standalone.
And before you suggest it, yes I have re-saved the permalinks several times.