[Lynne]

Put this line at the top of the template (with x, y, z changed for your condition):

<vb:if condition="is_member_of($bbuserinfo, x,y,z)">

Then put this at the bottom of the template:

<vb:else /> 
<div class="smallfont" align="$stylevar[right]">
You cannot see this title<br />Private
</div>
</vb:if>

You may need to modify the condition since it isn't clear to me exactly what your condition is supposed to be.