Two problems..

[DocRorlach 25]

Problem A:

Problem B:

[sim-Al2 4]

Now that would be a wild commute...

Anyway, this a known problem when two networks using the same path types cross over (or under) each other, commuters using those networks can "jump" from one set to another where they wouldn't normally be able to (like your rail over rail.) As far as I am aware, this could not be fixed except by modifying the .exe, which EA has kept under lock and key for a while now...

And the second problem is that those kind of cars are slightly too long to work perfectly on curves, although personally I still like them anyway.

[Deathcat001 8]

Yeah the overpasses are not actulay overpasses there just and eyecandy intersection. I have the same problem where cars float from one side of an interchange to another. 

[Darth Apple 54]

The "Trumpet interchange" has this same problem, you might consider tunnels, or a straight overpass. perhaps removing the train mod that you have might help with problem B.

I hope this helps.