Help with Accessible News Slider using jquery

I am new with Jquery and found this script "Accessible News Slider " Online that uses Jquery to display scrolling content, developed by reindel.

I have implemented it on my site and works well but I need to have four items show at once and not just two (4 items arranged 2 by 2).
Is there anyone who can assist me?... The link to the script is here : http://www.reindel.com/accessible_news_slider/