I found that if the thread starter is by a user without a certain BBC permission,
it will pass the restriction to anyone that replies.
For instance:
Registered Usergroup cannot use [IMG] BBC
Registered User creates a thread in which an Admin (who can use [IMG]) replies.
If that admin reply contains an [IMG], it will not parse.
Does anyone have the same problem?
I used [IMG] as an example but the BBC in question does happen to be custom.
sidenote:
I also tried the misc.php modification
as per this post
and received an error at the top of my browser when viewing the BBC list page.
Warning: sprintf() [function.sprintf]: Too few arguments in /includes/class_bbcode.php on line 1115