Your display issues are caused by the table for the center wrapper. The table does not close until after right column.

<table width="100%" border="0" cellspacing="0" cellpadding="0" id="contentMainWrapper">

then <td class="columnRight" id="navColumnTwo" style="width: 150px">
then <div id="navColumnTwoWrapper" style="width: 150px">
then <td class="FarRight"></td>
then <td class="RightBottom" align="right" height="26px" >
Then here is your table close tag </table>