How To Replace Default Module To New Custom Hook

[SeeJ]

Hi, does anyone can help me to figure out what I'm doing wrong?
 

I'm tring to modify "Products in the same category". I want to replace it to another hook in my theme.

 

I've copied the module to a new folder (from "productscategory" to "productscategory_mod"  and renamed module's class, files and so on...

 

Also in productscategory_mod.php
I have changed $this->registerHook('productfooter') 

to $this->registerHook('displayFooterProduct2')

 

I've changed name of the function "hookProductFooter($params)" to "hookdisplayFooterProduct2($params)"

 

And

In product.tpl added {hook h='displayFooterProduct2'}

 

But module does not appear...what I forgot?

Original "Products in the same category" uninstalled. In DB _hook all ok....

If I'll write return "Hello,world!"  in "hookdisplayFooterProduct2" function - it display's in theme