Routing mod

[Crashcast Evan]

Is there a mod that allows you to specifically route your trains on tracks? (Not route though waypoint)
That, Or a priority mod, like that allows you to set priorities to separate trains.

[Zakos]

If I recall correctly, it's possible to give priority to certain trains by clicking "Local" under the route tab; this will change the word "Local" to "Express."

As for your first question, all of the mods here are either vehicles, stations, or other add-ons, not changes to game mechanics. However, I don't fully understand what you mean so there may be a fix if you explain it a bit more