Q: I have a boxed version of The Witcher 3: Wild Hunt and I bought the boxed Limited Edition of Hearts of Stone expansion. Which platform should I redeem Hearts of Stone on?
A: Each boxed Limited Edition of The Witcher 3: Wild Hunt contains its unique GOG.com gamecode printed on the back of the manual. This code is compatible with GOG.com only and can be redeemed at http://www.gog.com/redeem.
Each boxed version of The Witcher 3: Wild Hunt – Hearts of Stone expansion contains its unique GOG.com gamecode printed on the leaflet. This code can also be redeemed at http://www.gog.com/redeem provided that the base game is already registered on your GOG.com account.
TL;DR Boxed version of the base game can be registered only at GOG.com. If you have a boxed version of the base game, you must register your expansion at GOG.com.
Q: I’ve got my base game registered at GOG.com, but want to register my expansion on Steam or Origin. Should I use http://thewitcher.com/exchange?
A: Definitely not. Such an action will render your original GOG.com game code invalid, and your new Steam/Origin code won’t work without the base game on the same platform.
TL;DR Do not use http://thewitcher.com/exchange if your base game is registered at GOG.com! We cannot revert the code exchange – we have no administrative power over Steam and Origin codes and are unable to annul them.
Q: I have a digital copy of The Witcher 3: Wild Hunt on Steam/Origin and I bought Limited Edition of Hearts of Stone expansion. How can I make the GOG.com game code compatible with my platform?
A: If your base game is registered on Steam or Origin, you can exchange your Hearts of Stone GOG.com gamecode at http://thewitcher.com/exchange to one compatible with your platform.