SmartCrawl Fatal Error

Hello, I've tried installing some of your plugins and now getting the follow error:

Fatal error: Only variables can be passed by reference in /var/www/vhosts/stirks123.ehost-services202.com/stirksbutchers.com/wp-content/plugins/wpmu-dev-seo/includes/admin/templates/underscore-macros-list.php on line 5

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