Hi

Here is how I have done it.

First set the NodeSelector="-1,0,1" in your skin.

Then in the ULTokens.txt file change the logic that displays the submenu as follows (i've changed < and > characters and replaced with { and } otherwise the code is removed):
From:
[?NODE]
{div class="subLevel"}
{ul}
[*>NODE]
{/ul}
{/div}
[/?]
To
From:
[?SELECTED] [?NODE]
{div class="subLevel"}
{ul}
[*>NODE]
{/ul}
{/div}
[/?]

Hope this helps.