Hi,

I’ve go to file: app/code/local/Sns/Avan/Block/Navigation.php find and replace the bellow code:

if ( $flatHelper->isAvailable() && $flatHelper->isBuilt(true) && !Mage::app()->getStore()->isAdmin()) {
By:
if ( !empty($flatHelpe) && $flatHelper->isAvailable() && $flatHelper->isBuilt(true) && !Mage::app()->getStore()->isAdmin()) {

Your website work well now. It seem that code is not perfect for if function. I’ll study it and update in next version

Best Regards!