Well I am here to report 2 other problems with feedback.
1) I am trying to leave feedback for a person who never replied in the for sale thread, which is now closed. I entered the url, typed in all the fields, and it said I can not leave feedback for that thread unless I created the thread, which I did.
2) On another deal (completely separate) I entered all the fields, clicked on submit, it said my comment was too short, so I corrected the length of the comment, and now says I have to wait 10 hours before I can submit feedback.
I am reporting these bugs, so you'll know about them and hopefully resolve them. Obviously restricting feedback options (IMHO) is more hassle... ANYWAY: now you know about 2 issues. On the first one, the buyer never replied directly in the thread, he PM'd me directly where we finalized the sale. And now I can not leave him feedback at all.