Joomlla tags problem.

When I click on a tag in Joomla articles are receiving the following error. The label is not displayed correctly.

Warning: strpos() expects parameter 1 to be string, array given in /home/public_html/bgpredpriemach/templates/gk_twn2/lib/gk.framework.php on line 642

I have another question. How to align center intro and Full Text Image in the article. Now they are aligned only on the left. When you select NONE, image it remains aligned to the left.

Thanks and greetings to your beautiful templates !!!

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Joomla! 3.1.5
PHP Built On Linux hook.icnhost.net 2.6.18-348.3.1.el5 #1 SMP Mon Mar 11 19:39:25 EDT 2013 x86_64
Database Version 5.0.96-community-log
Database Collation utf8_general_ci
PHP Version 5.3.11
Web Server Apache

Please configure your server according to Joomla! requirements so disable display_errors option in PHP configuration. More about this here >> Quickstart Installation Problems – How to fix them?