Thanks, I'll take a look at the signals issue. It's possible I accidentally broke pat of that logic when adding the new stuff, but it's also possible that it seems too long because there aren't many active trains. I'll look into it and make sure it's behaving correctly :)
If you're interested in some under-the-hood context; the reason it's inconsistent is because trainsaver only goes to a new train when a new train leaves a station, so if your current train is stopped at a signal but no trains are leaving stations, the camera will stay with the stopped train until it starts moving again or a train leaves a station.
It's actually the same logic for all the "waiting" conditions. trainsaver doesn't actively go find a new train to follow, it just waits for new train activity (trains leaving stations) and then if all the conditions of the currently followed train are right (it's been waiting at a signal for the minimum time, it's been driving for the minimum time, it's been stopped at a station for the minimum time, etc.) the camera goes over to the new train, otherwise it stays with the current one.