I’m not 100% sure about this, but I’ve come up with this kind of error before when I tried to loop two different overlays using the same line of code. I suggest separating the two into different lines, but still having them occur simultaneously.
If you are unsure of how to create a looping pause for an overlay so that it’s shift won’t occur until a later part of the animation, you can do this:
&overlay NAME shifts to [exact same position as it is already in] in T then …
This will make the overlay move for however much time you allot, but since it is moving to the same position it is in, it will act as a stationary pause for the overlay.
I hope this helps.