You can also offset the position by the Control rect size if you need to modify the position, though manual adjustment can be difficult with different screen sizes. I think the code I normally use is something like this:
func set_center_pos(new_pos):
$control.rect_position = new_pos - ($control.rect_size * 0.5)
I don’t remember if the offset needs to be added or subtracted right off, so you may need to adjust.
