I'll just delete my earlier post text and start fresh, since it was getting a little long and messed up....
So, as per my understanding of your response, I tried running the complete round trip, running in service from U Rathaus Spandau to Schulstrasse, then deadheading not-in-service from there. The run to Schulstrasse was fine. But then it wants me back at S+U Rathaus Spandau immediately, with absolutely no travel time whatsoever... Fine, so I blank out my destination sign and run back to S+U Rathaus Spandau as quickly as I can... Get there, and next it wants me back at Haupstr enroute to U Rathaus Spandau... Quit OMSI at this point, since I didn't want to do another complete round trip just to finish one scheduled round trip...
Am I missing something here?
No, no, no, sorry, my post was just explaining that the final stop shown on the in-cab timetables "Schulstrasse" equated to the route destination "Doberitzer Weg".
.....The part where the tour goes from Schulstr, straight to Rathaus Spandau (with no time break) is indeed an error on that tour. The Tour that is supposed to follow your initial run from Rathaus Spandau <=> Doberitzer Weg (Schulstr), is supposed to be the return journey; Dobertizer Weg <=> Rathaus Spandau.
When assembling tours, it's easy to 'select' the wrong leg within the editor, as has happened in that case. I'm sure Mr Drive will address the few timetable anomolies (there are a couple of others in the tours) in good time. In the meantime, on this tour, upon reaching Schulstr, you can temporarily cancel the timetable in OMSI, and then do the return leg (back to R.Spandau) without a timetable loaded. When you get back to R.Spandau you can then reload another suitable timetable, time-wise.
Hope this helps.