[Custom Service Integration] How to integrate Freshmail

Hi,

congratulation on the awsome plugin! ??
I need to integrate mail service Freshmail with the plugin. From Freshmail I get this code. How do I fill all the necessary fields in Custom Integration?

<form method=”post” action=”https://app.freshmail.com/pl/actions/subscribe/”><br />
<input type=”hidden” name=”subscribers_list_hash” value=”gaecpsfzhv” /><br />
<label for=”freshmail_email”>Email</label><br /><br />
<input type=”text” id=”freshmail_email” name=”freshmail_email”/> <br/><br />
<input type=”submit” value=”Wy?lij” /><br />
</form>