So, I would love to see a video or Pics of your setup...... I used the octobanger to run the whole sequence. Each side of our train had multiple 24" monitors installed which were dressed up to look like windows. When the sequence starts (hidden button mounted on one of the train car walls), the octobanger would trigger two Raspberry Pi video players (one for each side of the train car) to start playing footage of country side going by. A few moments in, the overhead lights would flicker and the "windows" would show Dementors attacking the train. A Hogwarts prefect would come in and perform the Patronus charm (blinding work light would pop on) to banish them. Then off to the Haunt they went!