Hi,
for this, you need several things:
1: Create a guiskin
2: modify the label entry
-- alignment: MiddleCenter
-- Stretch Width: true
-- Stretch Height: true
3: set this skin for your state using action "set Gui Skin"
4: using the action GUILayoutBeginAreaFollowObject to have your gui follow an object
5: set the area of this action above like so
Offset Left: -100
Offset Top:100
Width : 200
Height : 200
Normalized : False
3: add your label inside this area
and you will have a perfectly centered label on top of your object.
Bye,
Jean