[Plugin: Audit Trail] CSV Export Error

I am unable to perform a .csv export. I have played with folder and file permissions with no luck. I receive the following error when trying to download as .csv:

Server error
The website encountered an error while retrieving http://www.hpn-openitup.com/wp-content/plugins/audit-trail/csv.php. It may be down for maintenance or configured incorrectly.

HTTP Error 500 (Internal Server Error): An unexpected condition was encountered while the server was attempting to fulfill the request.

Help would be greatly appreciated.

Thanks

http://wordpress.org/extend/plugins/audit-trail/