[Plugin: upPrev Previous Post Animated Notification]

After I read fr33think3r’s post I believeed that he was using custom types without any issues.
http://wordpress.org/support/topic/plugin-upprev-nytimes-style-next-post-animated-button-percentage-of-post-and-not-whole-page

To come to a conclusion I just added to the $args array after line 30: ‘post type’ => ‘any’,

foreach((get_the_category()) as $category) {
            $catIDs[] = $category->cat_ID;
        }
        $args = array(
            "numberposts" => -1,
	     'post_type' => 'any',
            "category" => implode(',',$catIDs),
            "orderby" => "date",
            "order" => "DESC"
        );

Now it works fine! Simple solution 😉