Do I get the table correctly, when I assume it would take up to three shots from 37mm from directly above to kill a KV-1? And up to 1.9 shots to kill it with 75mm - hitting the hull? that would mean you'd need a hit o the body - and does IL-2 figure in shell energy, e.g. if shooting close you get better results?

Good question. A long time ago I used to fiddle with this numbers, and decided that the better results were obtained by just changing the KV-1 upper armor to 30mm.
I redistributed it as a mod to play a campaign and so be it.
If you read a bit more on the upper text, is seems that it is supposed to be a question of probability, not really a full table based solution. But I can't get a clear view from that too.
It was easier to change the KV-1 value.
I also modified the minimum angle for AA artillery, so to diminish lag. They will only fire against flying objects, and not against land moving chiefs.