His program is buggy. It's not reading the grid incorrectly - it's a constant width of 32 bytes, but a window from thetop left is taken for the actual size of the playing field.
So, first bugfix to his source:
  for(DWORD grid_loc = 0; grid_loc < grid_height * grid_width; grid_loc++) {
should be:
  for(DWORD grid_loc = 0; grid_loc < grid_height * 32; grid_loc += ((grid_loc%32)==(grid_width-1))?(32-grid_width+1):1) {
And:
    if((grid_loc % grid_width) == (grid_width - 1))
should be changed to:
    if((grid_loc % 32) == (grid_width - 1))
With these fixes, it reads all the bombs properly.

Sorry but your program is reading the grid incorrectly.Minesweeper uses a grid with a fixed width of 32 bytes and the playingfield is takena s a window of that grid from the top left. e.g.beginner mode uses bytes 0 to 8 and skips bytes 9 to 31 per every 32byte row.* Fixing the program to read based on that patten shows thatMinesweeper only moves the mine if it happens to be the first squareyou click on. Apart from that, all mines are randomly placed at thestart of the game.
(* Actually it would use bytes 0 to 10, where bytes 0 and 10 are0x10 which is to indicate the border of the mine field, and bytes 1 to9 are the actual squares. but that's not really relevant to theanalysis if you're just &ing with 0x80 to find bombs.)