There seems to be a lot of downtime....the game is running on the background as I type this thread.

How do you pass time?

Is just normal?

I didn't experience whole lot of downtime during the game (I have played it from start to finish couple of times). During the day there is always something you can do. If not anything else then you can explore the train and eavesdrop people. Listening conversations will give you whole lot of additional information about the characters on the train and their motivations. Usually there is so much going on that you can't actually follow everyone and listen every conversation (without rewinding the time and replaying the segment again). Many puzzles require that you'll be in the right place at the right time and you can do that only if you follow what's going on in the train and where the characters are.

Only time when there isn't anything going on is at night when you have done everything for the day, but then you should go to your cabin and sleep and the time will fast forward.

Huh, I think my struggle was more with trying to get all the stuff I needed in time rather than making it pass faster, heh. But I didn't get too far into it either - as much as I love the setting and the real-time concept I can't stomach too much of Point-n-Click puzzling ><

Not sure if it waste much time but I think you can go to the smoking part of a car and smoke a cigarette.