If you’re starting the scene with the overlay already included (which is what you seem to be doing), you have to specify the coordinates of the overlay to determine where it’ll be at the beginning of the scene.
E.G.
INT. BACKGROUND - DAY with LIVE to % x y in zone #.
Then, after the scene has started, you can code:
&overlay LIVE shifts to x y in (time)
AND / OR
&overlay LIVE scales to & & in (time).
(This is just to make the overlay move / scale around, unless you only wanted to place the overlay in the correct placing for the scene.)
Here’s a guide for more information: 