I think I've discovered a synchronization problem, or perhaps a disconnect between session editing/route editing and straight out route editing.
I have an ongoing route on which I added a small branch and I have two sessions. One session is for freight and the other for passenger due to the obvious kind of workings to be done.
A small branch runs to a quarry, off the mainline, which upon testing, proved to be a bit too steep to haul the aggregates from the pit. (The locomotives actually stalled!).
Since the branch exists in both sessions, I decided to edit the route in Surveyor, the old-fashioned way, rather than in a session via Surveyor-mode from one of the sessions.
Upon checking the individual sessions, the changes did not appear.
I exited and went back into Surveyor off the main menu, the old-fashioned way, and my changes were there just as I had made them.
Since they didn't exist in the sessions, I edited the freight session then jumped into Surveyor via Surveyor-mode, made the changes, saved, and exited. The changes now were there, but did not exist in the passenger session. I then repeated the process again in the passenger session, but upon checking the route again in Surveyor (the old-fashioned way), there were now two tracks slightly overlapping since I now had two edits in the same place! I cleaned this up and checked the individual sessions, and everything was fine afterwards (I think).
So something ain't right here. Theoretically if something is changed via Surveyor-mode, the same changes should occur across the board and be applied to the route, and appear when the route is edited "normally" as well as in any session that is base upon that route irregardless of what session was used to edit the route.