I got blank page as well. I checked extension=mysqli.so and it is enabled /etc/php.d/mysqli.ini. I set permission 755 for tastyigniter (/home/mywebsite/public_html/tastyigniter) and sub directories.
PHP 5.6.17 (cli) (built: Jan 9 2016 13:24:44)
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Zend Engine v2.6.0, Copyright (c) 1998-2015 Zend Technologies
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SOLVED: I need to change group/owner as well.