The Blue Comet add-on pack recreates the excitement and splendor of this remarkable train. Stunningly detailed and making use of up-to-date smoke, sound, physics and script features, the Blue Comet promises to be a satisfying addition to your Trainz collection.
Open the Steam client, login and locate the Games tab on the top menu. Click this and then select “Activate a Product on Steam…”
Enter your unique code that's displayed on the 'Orders' page of CDKeys.com and follow the prompts to activate.
Your game is now viewable in the “Library” tab and is available to download/install when you’re ready. You can find additional support for the Steam client here: https://help.steampowered.com/en/wizard/HelpWithSteam