Magento createBlock function
I want to create menu bar on my custom page
this code does not create block


    $block = $this->getLayout()->createBlock('catalog/navigation')->setTemplate('catalog/navigation/top.phtml');
    $this->getLayout()->getBlock('head')->insert($block, 'top.menu', true);

in this case block was created but in another place, I want to create them at bottom of head block

    $block = $this->getLayout()->createBlock('catalog/navigation')->setTemplate('catalog/navigation/top.phtml');    
    $this->getLayout()->getBlock('head')->append($block);
Please, help.
Magento createBlock function
===

I want to create menu bar on my custom page
this code does not create block


    $block = $this->getLayout()->createBlock('catalog/navigation')->setTemplate('catalog/navigation/top.phtml');
    $this->getLayout()->getBlock('head')->insert($block, 'top.menu', true);

in this case block was created but in another place, I want to create them at bottom of head block

    $block = $this->getLayout()->createBlock('catalog/navigation')->setTemplate('catalog/navigation/top.phtml');    
    $this->getLayout()->getBlock('head')->append($block);
Please, help.