[Plugin: WordPress HTTPS (SSL)] Force SSL Exclusively doesn't work

I’m hosting with Godaddy on a dedicated server with SSL certificate. The site defaults to https:// accordingly. I downloaded your plugin to force http.

The problem is that my site doesn’t render correctly when using https:// so I would like only the shopping cart checkout page to be https:// and everything else http://

Do you know why when I manually type in https://mydomain.com in my browser address bar it still allows me to access the https:// version of the site? I would need all pages to redirect to http://mydomain.com no matter what… except for the shopping cart checkout page of course.

http://wordpress.org/extend/plugins/wordpress-https/