Create a "subway wagon", a "detailed steam engine" and "box wagon" (or
any other unpowered wagon). Couple them together with the "box wagon"
in the middle. Now board the "subway wagon" and set the whole thing in
motion. You will hear the sound of the steam locomotive too but you
should not (the steam locomotive is not moving with its own power
I found this while moving my steam locomotive using the "subway wagon"
as I wanted to move both to a different location.
as of now, every engine in a train serves as engine, regardless of whether it actually should support "remote controlling". this might be changed in the long term