From your description above, sounds like you didn't run the upgrade sql.
copy and paste the following in you admin -> tools -> install SQL patches
Code:
ALTER TABLE `testimonials_manager` ADD `testimonials_url` VARCHAR( 255 ) NULL DEFAULT NULL AFTER `testimonials_title` ;
Those options were deliberately left out because of privacy/spam issues.
No easy way to add extra fields without re-writting some of the code and making changes to the database table (
please note that this is being worked on for a future update)