for (y = 1; y <= Bottom; y++) {
  data = str([4,y]);
  for (x = 5; data != ""; x++) {
    p = pos(data, ",");
    if (p > 0) {
      [x,y] = left(data, p-1);
      data = mid(data, p+1);
    } else {
      [x,y] = data;
      data = "";
    }
  }
}