We still have problems with centering in crop mode.
For the test:-
I centered the image by pressing the joystick in non-crop mode then entered crop mode. I then pressed the joystick again to snap to center and moved the camera until the cross was in center of the spot focus box.
I shot a couple of seconds at 2000x1080, 1920x1080 and 1920x818 (2.35:1) - repeating the centering process for each size.
I loaded the largest frame into photoshop and found dead center with the rulers, then drew a green cross.
I then loaded the other frames and positioned them relevant to the center of the canvas.
You can see that as frame width increases the offset pushes the recordable area further left so that the cross used for centering the camera moves to the right.
The frames with 1080 px vertical resolution also shift the recordable area up so the cross is moved down. This offset decreases with the 818 px height frame which shows there is a percentage based offset at work but the calculation is not yet correct for true (or nearly true) centering.

The image is 1:1 but has been cropped from 2000 x 1080 to show only the center portion.
This has implications for correct framing but having true vertical centering is vital when shooting with anamorphic lenses in crop mode.