After more that a dozen 40 day MCs and at least 10 years of sharing experiences on this forum I can tell you that the tongue thing is not a reliable indicator as to when to stop the fast. Some folks never get it at all and some will have it one day and gone the next The spot on the liver side of the tongue I would say is actually a good sign that your liver is detoxing. The wisdom is to continue fasting to allow the liver complete it's detox cycle.
If you are doing the MC by the book is highly unlikely that you are experiencing "real" hunger and it more a psychological issue . If you've been cheating even with the samllest tidbits all bets are off because you will have activated the digestive system and that will definitely make you hungry and or have cravings