Symptoms
How to bind a rule to the "new row link" and/or save the line automatically after a users presses enter on the last column and proceeds to the next line?
Diagnoses
There's not an out of the box way to bind rules to the 'Add new row' link.
Resolution
To save every time a user completes a new line, add an 'Execute another rule' action to the ' When the View executed List item added' rule, targeting the 'When Save ToolBar Button is Clicked'.
http://community.k2.com/t5/K2-blackpearl/SmartForms-Save-List-View-entries-when-a-user-completes-a-new/ta-p/90600