The original trackSubmit function automatically captures every single form field of a tracked form as a property in KISSmetrics. It also automatically identifies a user, if it detects that they filled out a form field with a name containing "email" or "username".
There are ways of forcing the function to ignore or include certain form fields, but for anything beyond that, you'd have to write custom JavaScript. The goal of this helper is to provide more configuration options when setting up form tracking in KISSmetrics, to prevent custom code from being required.
(Please see attached usage file for code sample)