Dump yabb. Go with a php based board. Burning board from woltlab is free. If you need it, just let me know. I have version 1.1.1 here and can email it to you. Also, the board itself is quite customizable and www.wbbhacks offers plenty of ways to improve the board itself with various hacks and customizations. The board itself is much faster than .cgi.

Just a suggestion though.