62: if a ball drains while the door is open, it'll be launched again once you close the door. useful in tournaments, or as a 'pause' button if you need to run off suddenly while playing
79+80: setting these lower makes the corresponding sound louder

212+213: how long the magnet engages to pull the ball around and up the left orbit when the ball is shot through the building. the game measures the speed of the ball, hence the 'fast'+'slow'

I'm not at home to be able to look at those kotm time attack settings, but they might have to do with the kotm time attack high scores and fastest times it had been completed.
The coin door setting, I always change it to "yes" first thing when I get a new Stern. I also change the setting to disable tilt when the coin door is open.
I mainly change those to fetch the occasional stuck ball and not mess my game up.

They are the KOTM time attack top 3 times. 1, 2 and 3 are the defaults and I agree, not realistic. It does give your time in thousandth of a second. Currently, KOTM time attach requires the topper or the internal node board ($200 on pinballlife) to play. The new code everyone is waiting on will have a KOTM mode. Either this time attack or some other mode format.
I too like going through and understanding the settings. It’s a shame stern does not provide this documentation