In the manual in section 2 the first field drawing shows the red secret passage attached to the red drivers station wall and the blue attached to the blue.
in section 2.1 it shows the blue secret passage attached to the red wall.
Which is correct?
Your secret passage will be in front of your castle. See fig 2-22.
My team was likewise confused by this, and we came to the conclusion that the field drawing with the flag and secret passage of opposite colors is a top view, so the flag is not the color of the driver station. As mentioned above the driver station is on the same side as the corresponding secret passage, and the vertical flag is also the same, but it is not visible from the top view. Each castle has both colored flags, where one is vertical and the other is horizontal- if that makes any sense (you can see in the game animation that once the castle is captured, the flags flip). This is my guess, but I agree that it is very confusing!