Midday post on Riviera in the fifties is not working. I get the screen Edit and Exit and can't escape it either. Is there something I am missing there like wagons? It also says Tracks Bin in the error message.
Press F2 and in the dialogue that comes up hit "cancel". The tracks.bin messages usually happens when something has been modified with the trains or route, but you should be able to use that workaround without anything breaking.