Don't bypass anything, it's too dangerous and you could have serious problems.
RE the orig issue, there is no hot or glowing ignitor with a spark ignition. If it lights at all it means the ignition cycle proves ok and powers the gas valve. When it goes out it's probably losing the flame signal which still could be a "lean" flame so try closing the shutter a bit. Make sure you do this before replacing the board. If all else fails, google the part number on the board and you will prob find one on ebay, which is what I did and paid half of the new $125 cost.
