While I still don't have the UI enabled for disabling certain codes, you can modify the method do_markup() in /libs/html.inc.php and add
PHP Code
$this->bbcode_parser->disallow_tag("spoiler");
The postcount is a global setting.
As for limiting graemlins, this would only be practical for users using php 5.1, otherwise we'd need to slow down the parser by parsing each graemlin separately.
