Web to Lead Integration with Google Sites

Web to Lead Integration with Google Sites

I tried posting this earlier but the post disappeared. We are using Zoho CRM's web to lead integration with our Google Site. As a basic setup, it's working okay but we need to be able to capture which contact form the user filled in so we know which content they downloaded.

There are various methods for this which all seem to require editing the HTML. Google Sites doesn't care for us editing the HTML and in fact rejects our changes, saying that there are invalid tags which are then removed. As a result, we get the contact form gadget but the hidden field doesn't work correctly.

Is this not a feature everyone else needs? Perhaps there is a way to do this that I just haven't figured out? It seems that we should be able to do this with the feature that publishes the page to the Google Site.

Thanks.