If you put WordPress into debug mode with:
define('WP_DEBUG', true);
You may get the following warning
"Notice: Trying to get property of non-object in /yourpath/wp-content/plugins/yet-another-related-posts-plugin/includes.php on line 274"
This appears to be caused by this single line of code:
$type = ($post->post_type == 'page' ? array('page') : array('post'));
My interpretation of the above code is that it attempts to set the variable $type based on the object $post. However, $post may not actually be an object, if for example you are viewing a regular WordPress page.
By rewriting this code with the an is_object($post) test, you can avoid this notice.
Please note: this also seems to address the following warning:
WordPress database error: [Unknown character set: 'utf']
set names utf-8