I have categories set up and want to copy the "Instructions" discussion to all the categories. Is there a way to do it? I can see the way to move a discussion.
There is no way to do that. I would recommend to use a message for that. Put that discussion in an appropriate category ("Help", "Feedback", "F.A.Q.s", whatever) and go to the dashboard and create a message with a link to the discussion.
My personal opinion is that this message should be "dismissable". Instructions are only for those who are new. Why should a regular member have to face the instructions on and on and on and on...
You can move a disscussion once and again and leave a redirect links in all categories you need.