RegisterPlus plugin width problem

I’m a newbie and need help with RegisterPlus – it shows up simply as a narrow single column, and it’s messing up how the radio buttons, etc. display. Anyone know how to get it to be wider, and display the radio buttons, etc., properly? Here’s the page in question:
https://66.147.240.182/~nrbmlcco/wp-login.php?action=register

By the way, I am using WP 2.8.4

Thanks!