So I've been working on a track for the last few months and have added multiple TSOs. (Stands, flagbox, a couple buildings) Just opened the track again today to work on it some more to be presented with 0 TSOs. No stands, no flagbox, no buildings, all gone. Added some vehicles, the flagbox and a flagger, saved, closed and reopened the track and... nothing but the flagger remained. Can anyone can explain why this suddenly happened and how I can stop it from happening every time I open a track?