They should be available as fast downloads from the "Train Store" button on your launcher once you get TRS22 installed. Everything you have purchased from N3V including locos, rolling stock, routes, etc. should be available.
To add to what @Forester1 has posted (just beating me to the Post Reply button) It is not recommended that you do a file transfer of DLC or built-in assets via .cdp files. This will cause problems.
Use the Content Store from the TRS22 Launcher as suggested above.
