Nice photos, Kenw. And while not intending to be in any way critical of your efforts, I would like to use them to point out to folks the shortcomings of using a macro lens in model photography, as I see too often done.
You'll notice that except for the box car photo, all the images have a particularly limited depth-of-field, with both the foreground and background out of focus. This is dramatically apparent in the first two images and still quite apparent in the third. It is a reflection of a limitations of most marcos when used for this sort of imaging.
In general, macros are intended for shooting objects in a single plane set at 90 degrees to the camera's lens and intentionally create a sharp image of the intended subject set within a soft foreground and background, when used for extreme close-ups. This is great for photos of individual flowers, insects, etc. but a poor choice when you want to photograph a layout scene of any real depth.
Marcos are much better left to do specific close-up nature shots and avoided in model railroad photography. Modeled scenes are
much better rendered when using a conventional zoom lens set at its minimum range (i.e. 18mm on an 18-55mm lens) and close to minimum focus, along with shooting at the greatest f-ratio setting (i.e. f/22 or more).
By way of example, the scene below is about 4-5 feet deep but the the shot is almost 100% in-focus. It was taken at 18mm focal length and f/32. The same scene, if shot with a macro lens, would have resulted in just the front of the locomotive being in-focus!
The moral of the story is that you should generally avoid using a macro lens when shooting scenes on your layout. On the other hand, they will do a nice job making "builder's photos" of various locos and rollingstock if they are placed parallel with the camera.
I hope you don't mind my using your nice shots to illustrate an important point.
NYW&B