Zift123 is not able to report email clicks and opens for emails you send from alternate email service providers (MailChimp, Constant Contact, iContact etc.)
If you choose to send your Zift emails from another email provider, the only data that Zift is able to capture is visits from the email to a published web plugin, stand alone microsite, or piece of collateral. These would be recorded as web views in Zift123, but would not indicate that the visitor came in from the email.