how to define ECK form url
Assuming you have a module called 'helloworld', and entity type called 'vechile' and a bundle called 'car'.Here is some code that should do the trick.

/**
 * Implements hook_menu().
 */  
function helloworld_menu(){
$items['feedbackform'] = array(
'page callback' =&gt; 'example_my_eck_form_page',
'access arguments' =&gt; array('Access feedback form'),// permission
'type' =&gt; MENU_CALLBACK,
);
return $items;
}

function example_my_eck_form_page(){
   module_load_include('inc', 'eck', 'eck.entity');  
   $bundle_name='car';
   return eck__entity__add('vechile', $bundle_name);   
}


function helloworld_permission() {
   return array(
    'Access feedback form' =&gt; array(
      'title' =&gt; t('Access feedback form'),
    )
  );
}


Access feedback form is a custom permission so you still would have to give that permission to the  users from admin to be able to access the path.