I have had more games than I can count in which I had overwhelming material advantage & the server stops the game & declares it a draw (usually when my opponent has only a lone King), because of "insufficient mating material." I would assume that when one side is down to a lone King, a glitch in the program makes the server think that both sides have insufficient mating material.

No, if you run out of time and the opponent has a lone king, it is a draw.

For example, this game:

White cannot win, he ran out of time.

Black cannot win, he has no way of administering checkmate.

A draw is the result.

Thank you for your comments. I will be sure to check whether I have run out of time in the future when the server declares the position drawn.

yes happens to me all the time! It is the danger of playing Blitz you do all the work and can even lose by a fraction of a second or draw when te guy has not a prayer!