Triggering e-mail upon change of status of a custom object

Hi, everyone, We're starting a project to integrate eSignlive into the salesforce org of a customer in my company. While checking the documentation, we've seen that this specific part is pretty useful to us: http://docs.esignlive.com/content/e_classic_application_user_s_guide/signers/receiving_esignlive_packages.htm?Highlight=tablet%20desktop#Mobile2 It comprises more or less what we'd like to have at a point of our process: an e-mail with a link to sign the document and take it back to salesforce. However, at least two doubts are arising before we decide how to tackle this: 1- Is it actually possible to trigger the submission of that e-mail upon the change of status of a custom object? If that's the case, some info would be useful, since in the link I shared I can't really find this and I'm not sure where to find it (a link would suffice :) ) 2- In the link I shared, apparently, two e-mails are requested if we prefer the approach of "drawing on screen" signature (one initial e-mail to see the documents and another one when the user decides to sign). Can't this be merged in order to avoid the second e-mail? Like, for example, making the button to sign take the user to the signing page directly, without needing that second e-mail. Thanks in advance and sorry if this isn't the right forum to post this.