Kunena Discuss is a great plugin for using the Kunena forums to discuss front-end articles. The problem is that if you want that forum dedicated only to comments and replies on the article and no "New Topic" allowed from within the forum, Kunena 1.6 doesn't support this. It's not enough to tell people not to post new topics in those forums because, well, they just do it anyway! After wracking my brain cells trying to figure out how to do this, (and being told NO by the fine folks at Kunena) I stumbled across the "By URL Parts" section of the CBSubs manual. Lightbulb. Here's what I'm doing...

In CBSubs I created a dummy plan that isn't visible to members anywhere and can't be upgraded to. In its "By URL Part" editor, I added the Kunena New Topic actions for each category that I wanted to be reply-only:In the language file, I edited the warning that reads "Access to this location not allowed without %s" to be:

"You have reached this page because you are trying to post a New Topic in a Reply-Only forum. To create a new forum topic, blah, blah, create a new article, blah, blah"

And it works like a charm. I was afraid CBSubs might block Kunena Discuss from posting new topics as well, but I guess since it's not a "user" it allows the new topic as it should. Hope this helps others that may need this function!