All may not be lost here if you still have your old computer. What you need to do is open up the c:/Users/LOGIN NAME/app data/local/N3V Games folder.
Look for a folder named Build-something.
The something is an alpha-numeric sequence.
Copy the folder to an external drive. The One Drive will be a bit too slow given the size of the data folder.
After copied...
On the new computer...
Copy the build-something folder to your local hard drive. Note this folder does not need to be in the App Data location. You can even rename it and put it on another drive, which many of us have done. I put mine on my E: Drive, for example in a folder called TRS2019_DATA so it's easy to find for backing up, and editing.
Once copied...
Start up TRS19 on your new computer.
Click on Trainz settings on the Launcher.
Click on the Install tab.
Click on the ... next to the white box with the old path in it.
Browse in the File Explorer window to where your copied data folder is located.
Click on Select.
A brief window will appear like a database repair and you'll have to restart. Once restarted, you should be all set if you followed the steps.
For backing up. You simply copy the data folder to your external location. A One Drive maybe too slow for your data which can grow over time with downloads and DLC. This can be a problem copying over the internet, and it's for this reason I recommend a local backup drive such as an external drive by Western Digital or Seagate instead.
