Note also that there is a very odd rule: if you miss a question in round one, 10 seconds are deducted from your time. If you miss a question in rounds two through four, a miss is a five-second deduction. Hence, appropriate strategy is to use all three of your passes in the first round if you aren't reasonably sure of your answer.
As for factual inaccuracies, I'd definitely say that not accepting ".5" as the decimal equivalent of 1/2 falls into that category (I had that experience as well). I'm fairly sure that it deducted for a correct answer on one of their multiple-choice questions, but the nature of the game being what it is, I can't be 100% sure, nor can I remember the question well enough to verify.