I had to change mine to 94% to get it to line up properly. Maybe that's just the way it lines up using firefox?
Anyway at the very top line of the chess template change the 100% to 94% or 95% or whatever works for your site.
Code:
<table class="tborder" id="post$post[postid]" cellpadding="$stylevar[cellpadding]" cellspacing="$stylevar[cellspacing]" border="0" width="94%" align="center">
It's already aligned center.