I posted a background image tag in like you mentioned in css and it should be right over the username,password area but i cannot see nothing. Is their some background that needs to be transparent?
Location - Vertmenubox.
<TABLE border="0" cellpadding="0" cellspacing="0" width="100%">
<TR>
<TD class="VertMenuBorder">
<TABLE border="0" cellpadding="1" cellspacing="1" width="100%">
<TR>
<TD class="VertMenuTitle">{$link_begin}[img]{$ImagesDir}/{if $dingbats ne ''}{$dingbats}{else}spacer.gif{/if}[/img]{$link_end}
{if $link_href}
<FONT class="VertMenuTitle">{$menu_title}</FONT>
{else}
<FONT class="VertMenuBoxNewsTitle">{$menu_title}</FONT>
{/if}
</TD>
</TR>
<TR>
<TD class="VertMenuBox">
<TABLE border="0" cellpadding="5" cellspacing="0" width="100%" background-image: url("file/images/loginbglarge.gif")>
<TR>
<TD>{$menu_content}
</TD></TR>
</TABLE>
</TD></TR>
</TABLE>
</TD></TR>
</TABLE>