Related Field not work

Perhaps my mistake is in creating the relationships between modules?
I enter the studio - modules
New realationship
Module events one to one - module lead

this is my procedure

I tried this solution with a personal field, but it didn’t work
try again,
Ralationship one 1 one work ?

hook logico" after_save (not work)

<?php
// Do not store anything in this file that is not part of the array or the hook version.  This file will	
// be automatically rebuilt in the future. 
 $hook_version = 1; 
$hook_array = Array(); 
// position, file, function 
$hook_array['before_save'] = Array(); 
$hook_array['before_save'][] = Array(1, 'Value from one field to another', 'custom/modules/leads/my.php', 'User_hook','copy');
?>  

my.php

 class User_hook {

    function copy(&$bean, $event, $arguments)
    {

    $bean->date_start  = $bean->myfield_c;
    }

}