Looks like I'm little late for this one. How'd your game go, OP? For anyone else, I've played in a couple games and GMed a few as well. Here's what I've learned:
- As Leokadia said, learning into the ceremony is important. It's all too easy for players to break the tension with jokes, and the ceremony helps maintain that feeling of solemness.
- Whenever a candle goes out, feel free to fast forward to the next scene where something dramatic will happen. I didn't do this, and just kept going into the next moment. After the fact, I felt like things would have been more interesting if I had kept things moving.
- it's easy to forget, but remember that everything is dark. Your players will need to figure out how to see where they are going. If you need a quick way to ramp up tension, you can threaten their light source. Don't do this too often though.
- Take a bathroom break before play begins. It sucks when you have to pause the game at a tense moment, and then you may be faced with the fact that a light or two went out in your absence