Compare the Openbve Route selection menu to the BVE 5 Scenario menu.
Now the difference is obvious On BVE 5 there is no drop down menu. You have to select the route as-is.
Now that you Know BVE 5's major change lets start off the tutorial.
So to start off, here is the Scenario text file that comes with Mackoys package route "Keisei Chiba Line".
Okay now on this "txt" file there are 8 sections of text.
Title
The given title for the Scenario
Author
The author for the Scenario (Mackoy Minatono)
Route
The route name (Keisei Chiba Line)
RouteTitle
Usually a specific route, For example Hanzoumon Line B1367S
Vehicle
The type of Vehicle being driven (Keisei 3500)
VehicleTitle
Same as the "Vehicle"
Comment
Usually author comments or acknowledgements for other Devs
Okay now that you have familiarized yourself with the Scenario "Txt" file structure i'll show you how to change the Train.
First off look for the "Vehicle" text section
Delete the all the text for the "Vehicle and Vehicle title text lines"
Now replace both text lines with the desired train and destination folder titles. In my case i will use the Tokyo Metro 7000 series.
So i replaced the two text lines with the source folder and the train name.
Here is what i wrote if you can't see it.
Vehicle= Segtor\tokyometro7000f\Vehicle.txt
Vehicletitle= tokyometro7000f
The "Segtor" is the source folder and the trains title is "tokyometro7000f". The "txt." is the text file for the train. Most train text files will have a different designation.
Example
Vehicle= Kazuma\209-2100\Vehicle_4M2T.txt
Be careful train text designations can be different and sometimes you might accidentally put the "Readme" text instead of the Train text.