I can get the layered nav to appear in one column content using the following code but how do I control the vertical positioning? - at the moment it appears at the top no matter what I do. The category page is set to display a static block only.
<reference name="left">
<action method="unsetChild"><name>catalog.leftnav</name></action>
</reference>
<reference name="content">
<action method="insert"><child>catalog.leftnav</child></action>
</reference>