Fatal error: Uncaught exception 'Zend_Feed_Exception' with message 'Invalid parameter: "name" must be a non-empty string value' ../library/Zend/Feed/Writer/Feed/FeedAbstract.php on line 122.

Once that's fixed we get another exception:

Fatal error: Uncaught exception 'Zend_Feed_Exception' with message 'Invalid parameter: "name" must be a non-empty string value' in ../library/Zend/Feed/Writer/Entry.php on line 119

This is due to code that won't ever work.

Patch

Change line 120 in Zend_Feed_Writer_Feed_FeedAbstract to:

if (empty($name) || !is_string($name)) {

AND

Change line 117 in Zend_Feed_Writer_Entry to:

if (empty($name) || !is_string($name)) {