Jeremy, here's a tidbit which will probably get you started.

Example - in showflat.php we have this:
if ($reply == "on") {
$postrow[$i]['replylinkstart'] = "<a href="{$config['phpurl']}/newreply.php?Cat=$Cat&Board=$Board&Number=$Number&page=$page&view=$view&what=showflat&sb=$sb&o=$o&fpart=$fpart&vc=1">";
$postrow[$i]['replylinkstop'] = "</a>";
$postrow[$i]['quotelinkstart'] = "<a href="{$config['phpurl']}/newreply.php?Cat=$Cat&Board=$Board&Number=$Number&page=$page&view=$view&what=showflat&sb=$sb&o=$o&fpart=$fpart&vc=1&q=1">";
$postrow[$i]['quotelinkstop'] = "</a>";
}
Try chaning that "if" line to something like this:
if (($reply == "on") && ($Board != "keyword") {
And put the board keyword that you don't want the reply link to appear where I have "keyword" above, then it should only show the reply link if the board is not that keyword.
There is similar code in showflat.

Hope that helps.
