M2ePro无法获得活动

Question

I'm trying to get an event triggered by a m2epro module, but my module seems to not be able to get it. I can't find where I'm wrong

Magento 1.9.3.10 PHP5.6

config.xml

 <models>
   <module_mod>
            <class>Module_Mod_Model</class>
    </module_mod>

  </models>

<m2epro_order_place_success>
  <observers>
    <module_mod>             
          <class>module_mod/observer</class>
      <method>myMethod</method>
     </module_mod>
    </observers>  
</m2epro_order_place_success>

Observer.php

class Module_Mod_Model_Observer
{
    public function myMethod(Varien_Event_Observer $observer)
    {
    Mage::log("I'm here,null,"event.log");

         return true;

    }
}

After the event is triggered, the module observer doesn't capture the event. There something wrong in this code?