Warning: Illegal string offset 'only_users' in…

Thanks for this good plugin !
I test it on my local php environment(wamp/php 5.4.3),get some errors like this:

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SCREAM: Error suppression ignored for
( ! ) Warning: Illegal string offset 'only_users' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'show_guest' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'button_in_home' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'own_button_type' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'dashboard_recent' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'dashboard_top' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'show_voters' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203
Warning: Illegal string offset 'ava_dsc' in E:\wamp\www\demo.wpdaxue.info\wp-content\plugins\kk-i-like-it\settings.php on line 203

What’s the problem ? How can I fix it ?
I would really appreciate your reply. Thanks again!

http://wordpress.org/extend/plugins/kk-i-like-it/