The Art Icon should be a side shot of the car or loco on a track with a black background that has a alpha mask that will knockout the background.
To do this I made a map with the one track going North-South and a white ground color with one side of the map having a large hill, this is basically a stdio product table. This is a one baseboard map and one Session with just one loco at the end and my new car or loco placed about 400' down the track, this way I can just edit the Session to replace the "old" with the "new". Run the Session, set the camera and "Sun" (my light) and hit Prt Scr.
This is the map.
And this is how the shot looks.
The Art Icon