I have found it hard to understand somebody else when they described their puzzles/problems. So I don't feel surprised when somebody find my description confusing etc. What seems obvious to one often turns out to be utterly nonsense to another. Even when the language barrier is not an issue.

Anyway, I'm not holding high hopes anybody else is solving these, so that's probably almost the "series finale". However, besides being computer programming exercises at least one of them is "human solvable, by logic and hand calculation", namely:

I wrote:3. The (Nearly Perfect) Anti-Magic Square

Fill all of {1..9} into a 3x3 square so that all 19 numbers from {1..19} appear either as a cell value or a sum/product of a row/column/diagonal.

I was sure someone of

RW's calibre could work it out elegantly... But no takers...