fixedlist w/conditional focusposition

Love a fixedlist for the way it scrolls but I'm not so enamored wth the way an empty container fills from the focusposition rather than the top.

Experimented with something like this:

<control type="fixedlist" id="50">

    <control type="group">

        <enable>bollean-that-checks-if-list-depth-greater-than-x</enable>

        <focusposition>y</focusposition>

        <movement>y</movement>

    </control>

    <itemlayout width="100" height="100">



    </itemlayout>

    <focusedlayout width="100" height="100">



    </focusedlayout>

</control>

Doesn't work but is something near to this possible?  If not, perhaps a forum member has some custom animation work that mimics fixedlist behavior and would be willing to share it?

Thanks!