You can be penalised for publicly disputing penalties/incidents, they are to be dicussed in private with the race manager.
NOTICE
Ok I am going to add a rule about challenging penalties. If you challenge a penalty and it is upheld to be excactly same as in the stewards report you will recieve a further penalty. This will encourage people to check the replay BEFORE they make an appeal and not just do it out of hope because if it is the same result it is a waste of my time. You must also put WHY you are challenging it.