DirectFB Overlay Help

I'm getting a little frustrated with the dfb overlay.  I don't think I
understand how DFBLayers come into play.  We only seem to have layer 0,
even after I create another surface.  What are the layers for?  For some
reason after I blit the overlay's surface to the screen surface it isn't
showing up.  The video plays to completion (you can hear the audio) but
not a single frame is displayed.

The xine driver changed the configuration of layer 0 at each
frame_format_update, which seems wrong to me (and DFB agrees with me, it
won't accept the change - see commented out section of the overlay_dfb
constructor).

If anyone has more dfb experience than I and can shed a bit a light on
this I'd appreciate it.  

Thanks,

Darren