Well, the reason I asked is because the code for your advertisements may be the issue.. But I just took a look at your websites source code.. Here are things that stand out to me:
This section:
HTML Code:
<!-- RIGHT COLUMN START -->
<td width="150" valign="top" class="page" style="padding: 6px;">
<td width="150" valign="top">
is what I think is throwing it off. It's putting a table cell between the forums and the advertisement which is why it's being pushed so far to the right.
Going from the instructions in the linked post, I'm not sure how that section of code got in there. You may want to double check your footer edit.
Hope that helps.