A little puzzle for scenario writers

[OldProf]

You're working on a complicated switching scenario called "Switch away". You've successfully set up and tested all of the player's actions. To add AI traffic, you've used the following sequence one train at a time: clone the original scenario, naming the first clone "Switch away 1AI", placing and scheduling the AI train, testing until it works, and then going on to the next AI unit. You've reached clone "Switch away 7AI", but suddenly player drop-off instructions stop working: while testing, you make a drop off on the correct siding but the F1 list shows an "X" instead of a checkmark. What has gone wrong and how should you fix it?

This little puzzle is based on personal experience and does have a solution.

[robbit]

Check the car #'s and besure you have dropped them all in the right place or duplicate rail numbers

[Chacal]

I was gonna say duplicate wagon numbers too.

[OldProf]

Good for you! Yes, the problem was caused by duplicate car numbers. To be more precise, some cars located in AI trains had the same numbers as those included in the player train's pick up or drop off orders. I've seen a few scenarios in which the cars of AI trains were assigned simple, sequential numbers (1, 2, 3, etc.) in place of the numbers chosen randomly from the list created by the cars' modelers or re-painters.

Kudos to Chacal and half-Kudos to Robbit, who gave the correct answer first, but made it more difficult to understand.

Follow-up questions: what's the easiest way to spot duplicate car numbers and to find out where the cars with duplicate numbers are located? (This is the step I lost track of in the real-life example on which I based this puzzle.)

[robbit]

Check the triangle error message icon on the bottom of the timetable screen and click on the number that is duplicated and it will show you on the left hand side.

[OldProf]

Excellent, Robbit. You obviously know your stuff. I started this thread to provide some helpful information to less expert scenario writers and those, like me, who sometimes forget what we've already learned. Yes, I let the duplicate car numbers gremlin fool me yesterday, but now my scenario's back on track (pun intended).

[robbit]

good idea. don't stop now I like it and everybody can learn and have fun doing it like this

[Chacal]

Check the triangle error message icon on the bottom of the timetable screen and click on the number that is duplicated and it will show you on the left hand side.

I must say I didn't now that one.