@mmatty - I just took a look at your form and it seems like it’s missing a bunch of things that Mailchimp requires for the embed. Make sure you choose “Embedded forms” in Mailchimp like I described above when you create your form.
@brryant thanks for your detailed answer
I was actually going about this in the correct way, the same way you suggested. But as Vlad from Webflow support was kind enough to discover and point out, I had a missing parenthesis there, and when I was publishing, Webflow got confused and fixed it by taking out the whole <form> tags
It seems to be working properly now.
My experience with Zapier is not that great. When a website visitor is on a landing page, and just filled out a form to receive something via email (Mailchimp autoresponder) you don’t want them waiting 10 minutes (5 minutes with the upgraded Zapier plan) for Zapier to fire and send the form data to MailChimp. You need that stuff to happen right away. It should never take more than a minute for data from webflow to reach MailChimp for an autoresponder to reach back to the website visitor.
Zapier is fine for building archived versions of form submissions, but not for the primary method of transferring data.