Error during posting question

Wp Version : 3.3.1

Hi when i post question, question is being posted but i'm receiving this error

Warning: include(/home/mehmetk/public_html/1/wp-content/plugins/qa/default-templates/single-question.php) [function.include]: failed to open stream: No such file or directory in /home/mehmetk/public_html/1/wp-includes/template-loader.php on line 43

Warning: include() [function.include]: Failed opening '/home/mehmetk/public_html/1/wp-content/plugins/qa/default-templates/single-question.php' for inclusion (include_path='.:disappointed:usr/lib/php:disappointed:usr/local/lib/php') in /home/mehmetk/public_html/1/wp-includes/template-loader.php on line 43

and i would like to use same style as what they have, just the while asking question, text bar is like this
http://www.szegedlek.com/1/questions/ask/ plus i just wantto change "search" button color cuz both background and button is white