So if the title didn't get your attention, keep in mind I have only been back in Trainz (specifically TRS19) for about 4 to 5 months. Transdem I believe it's been 1 to 2 weeks. For the most part I'm learning as I go and finding a system that works for me.
Start small! That doesn't mean you route has to be limited to a small area necessarily, just work on small areas at a time. You can still get a large route functional within a reasonable amount of time to operate and add the details later.
I already had about 20 mainline miles down in the Basemapz approach but a gift of a DEM file eventually lead me to wanting more and my purchase for Transdem has been worth every penny.
You can get plenty of detail in the UTM overlay files. I thought Google Earth was the only option, but Bing does a good job. Fort Erie which I'm starting at vs Port Robinson in my 1st route can handle both Level 19 and 20 UTM from Bing. However since 20 is not available everywhere I settled with 19. I was able to obtain in Canada 15M data from the government for free. the nearby United States USGS has 5 and 10M data depending on the area. It even includes, some but not all of my area.
Here I am in the 15M data and I'm right at the border with the U.S. Now this adds some complication which I plan on fixing tonight. But thankfully the border is in the Niagara River which is at an absolute height that is easy to fix with the fill technique.
I was able to load the entire raster images (all 400 that I downloaded the night prior as it will save the georef to 1 file). Here I demonstrate also why I like to start slow. The bigger amount of data, the more risk you are to errors in processing.
Here is the video
https://www.youtube.com/watch?v=vqUH-Jbqtk0I continue to do more on YouTube every night.
Thanks
Sean