I've had several people tell me that they cannot post comments. I have added the feature that you can post anonymously as well as subscribe via email. I was hoping that would help with commenting. I was WRONG!
The way to comment is to type the message then to choose the way to post. If you choose name/url, you do not have to have a URL, simply use your name. Next, click Preview. This asks you to type in a code. Then the post will be complete when you click the post comment button.
I hope this helps with posting comments! Have a great day!