Zoho Sign API lacking clarity

Zoho Sign API lacking clarity

I'm trying to use Zoho Sign to embed a document for signing into a web application, and the documentation is proving to to be lacking something.

Some issues...

1) No clarity if the API only works with a document uploaded through the API -- it would be nice if I could define the document in the UI, and just reuse it in the API

2) I use https://sign.zoho.com/api/v1/requests to create the document, but the response does not contain the actions that I included... but I need the actions for the embed phase... and the PHP example https://www.zoho.com/sign/api/embedded-signing.html which I replicated assumes there will be actions in the response.

3) I haven't yet found a description of the coordinate system -- what are "x_coord" and "y_coord" based on?