If a cart assembler is placed on a controller rail then that controller rail + cart assembler has a direction that they are facing. When a schematic is taken of this combo and mirrored, any mirroring is not preserved. Rotation is also broken, only works in one of the three rotation direction.

Tested with both the creative schematic print method and the schematicannon.

Image below shows the original (top left) and 3 rotations (rest of top row), and a mirror (bottom). The first rotation looks correct, but the second and third have the controller rail flipped of what is expected. The same error is present for the mirrored case.