Null Nullus - 2009-03-25

I'm a new user of Bookpiles, and love its ease of use. I'd like to save my own comments, though, and am having problems doing so.  I see that if you select a book, then click on the "Edit" menu option, a window opens that has a tab labeled "Comments". It's greyed out, though, and I don't see how to enable the function. Could someone point me in the right direction for saving comments/notes? Thanks