There is a bug in the MOS scoring. In moscolumn.js you are using the line:

var percentPacketLoss = LostPacketCount / TotalPacketCount;

which yields a value between 0 and 1. The algorithm you coded actually requires the value be between 0 and 100. Why they wrote it this way is beyond me, but the proper line would be:

var percentPacketLoss = (LostPacketCount / TotalPacketCount) * 100;

I injected up to 20% packet loss stepping up by 1% and the MOS score never dropped below 4.37 with the code you are using. Please correct and send out asap. The correction makes it come out correctly at a MOS score of 2.10