Hello!
I have this thread:
TIP: Rotating An Overlay Without Having it Shift Somewhere else 
- Creator’s Corner / Directing Help & Tips - Episode Forums (episodeinteractive.com)
Here’s an example. Basically if you don’t want your overlay to glitch somewhere else, you should place it like I did above in this example. I see you used anchor point 0 0 instead of anchor point 0.5 0.5 though.
But yeah, you should do this ^^ In my example code above, when I add the rotates to command to the overlay, it moves back and forth and doesn’t shift somewhere else XD