I understand where you are coming from; however, if I do the code that way, then it will show the signup page for everyone, no matter what usergroup or category. Logically thinking it should be OR, since usergroup is 1 and is not a member of usergroup 5, 6, 7, OR 8, then they should see the signup page. For some reason thought it is not seeing it that way and sends all groups to the signup page. The only way I can get it to function the way it is intended is to have the code the way it is.
Anyways... I have found the problem. It appears it as I initially had said with the way the URL changes after a comment is made. When my code is looking for the particular categories that are allowed, when the URL changes, apparently it doesn't know what category it is, so it sends the person to the signup page. I fixed it by changing the following line in comments.php from
Code:
Content visible to verified customers only.
to
Code:
Content visible to verified customers only.