I found this video on what looks like an exciting process for importing 3D models into Blender from Google maps and then into MS Flight Sim. I'm not a Blender user so I don't know if it can be exported into Trainz. But it is interesting. The good stuff starts at the 10 minute point.
https://www.youtube.com/watch?v=ZdCP11rqpVk
William
https://www.youtube.com/watch?v=ZdCP11rqpVk
William