If this is the first time the route has been loaded after a fresh install, then a precache will take a while to complete. A really large route will only compound this and will take a very long time to complete. Once completed, the route will load up much faster the next time it's loaded.
There are some things you can do to help.
If you're running from a regular hard drive, by all means defragment the drive. This really helps a lot.
Ensure you have plenty of disk space as that can slow things down quite a bit.
Finally, you can precache your content prior to running Trainz.
At the Launcher, click on Trainz settings.
Click on the checkbox to enable Dev tab and click on enable advanced debugging tools if you haven't already done that.
Close this window and:
Click on Developer on the menu bar on the Launcher.
Click on Run TrainzUtil Command...
This will bring up a dialog box where you can enter the command parameter you want.
In the space, put in:
prebuild --force --nofail
This process can take a very long time to run, and therefore it's recommended you run this overnight. Once complete, your routes will load up much quicker than they do if they have to precache the data on the first run.
