1 - my guess is the same as issettas - if the track before the sensor is at a different angle of elevation to the sensor piece, the front of the car may skip over the sensor and the signal be missed; or the guide may skip over the LC flipper. If everything is flat but raised, my guess is it will work fine. (unless it is a matter of light getting to the sensor from underneath?)
2 - blue flags - again I agree with the posts above, black is more opaque and therefore more reliable than blue. If you are getting reliable lane changes and lap counts with blue, don't worry about it!
2 - blue flags - again I agree with the posts above, black is more opaque and therefore more reliable than blue. If you are getting reliable lane changes and lap counts with blue, don't worry about it!