Hi,
You have to use a combination.
set your skin to alignment to "LowerCenter", and simply use a GUILabel quite simply. Leave the default rect set up ( normalized, 0,0,1,1). Then it will work just fine without any fanzy layouts that anyway would take performances away for nothing...
If you need a working sample, let me know, I have tested the set up above, so I know this works.
bye,
Jean