The Puzzle

Load game #1 puzzle from Will Shortz's Sudoku, February 2016, number 197
Load game #2 puzzle from Will Shortz's Sudoku, February 2016, number 196
Load game #3 an extremely hard Sudoku that must use Brute Force to determine that cell [0,0] must be 3
Load game #4 a puzzle that revealed a bug in Test 4 Row. Bug is now fixed.