I tried to connect Cornerstone Forms to Klaviyo with the External API, but struggled as it is outside my wheelhouse.
Please add a Klaviyo Subscribe Element to the Form Actions please. 
Hello @seanscott49,
I have noted this and added it as a feature request.
Meanwhile, if you are interested in having a custom integration built, please contact us here. Tell us more about the integration, and we can send over a quote.
Best Regards.
This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.