im trying to use
Posts Required To View Forum
on a sub forum.
but i don't know it id a little help?
When you go to the forum, you will see "forumdisplay.php?fid=X" at the end of the URL, where X is the forum ID.
That's because you're using a SEO Modification. The forum ID of that forum would most likely be 16. I believe the format is:
mmorpgspot-net-news-f-16.html
<forum name>-f-<forum ID>.html