how do you change the bbcode in the admin panel?like if I want it to be [right] instead of [alighn right]
You would need a modification for that. Try asking on the Code Modifications and someone might make it for you. You could also try over at
http://mods.mybboard.com
Instad making alignment tags for each alignment (right, left, center)
You can just make one and it'll work for all.
$message = preg_replace("#\[align=(.*?)\](.*?)\[/align\]#ie", "<span style=\"text-align:$1;\">$2</span>", $message);
IE. [align=right ]Text Here[/align]
Edit
But the bbcode is already in RC4