SmartCrawl throws fatal error on activation

When SmartCrawl is activate on site it throws fatal error:

Fatal error: Only variables can be passed by reference in /wp-content/plugins/wpmu-dev-seo/includes/admin/templates/underscore-macros-list.php on line 5

That is Single WordPress on PHP 5.6 - plugin conflict did not give positive results (error was still there).

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