Flashing top lane is the skillshot (for 100,000 x ball number). It opens the organ for multiball locks. There's no lane change.
Complete ONE on organ to light lock for 15s. Shoot organ for 2-ball MB. Shoot organ to open it, then lock both balls in organ for 3-ball MB.
During 3-ball MB, shoot the organ to open it, then shoot a ball inside for jackpot. Complete ONE and TWO on organ to relight jackpot.