ok, guys, my bad, seems to me I've updated the paging class after this mod was created...
So, try to replace in Step 1.2:$getpaging = new Paging($page, $perpage, $total, $link_arg, "cat_page", $cat_text);
with this:$getpaging = new Paging($page, $perpage, $total, $link_arg, $cat_text, "", "cat_page");