Newtonian mechanics shows that the entropy of a closed system increases or remains the same. No heat engine can operate at 100% efficiency but statistical thermodynmaics does not necessarily show that you MUST increase in entropy all times. It is a probabilistic statement. There is a probability that when you turn on the flame under a pot of water that the water will turn to ice. Sure, the chances are small, but there is a finite probability.

Time is not positive or negative in the equations for relativity and you will have the same results for positive time and negative time. Time, therefor has no direction. Direction exists in our minds only - multi-verse-iality just shows this. Now, with the idea of the multiverse existing in this state - time Would indeed have direction.....
R denis