Suggested fix (unconfirmed): Verify the game files and restart Steam. If that fails, manually install or check the DLC checkbox in the game's Steam properties.
The problem
where and how can i start playing the DLC?
What players suggest
I click the "DLC extra scene" it still bring me back to the dlc store page not start them, I already bought the DLC. I try everything from "property" to validate file, re-install the game and noting work.
Suggested fix (unconfirmed): Access the DLC via the "Extra Scenes" link on the right side of the main menu. If you are on Mac and the link fails to open, verify game file integrity through Steam.
No confirmed fix yet. Players suggest: If it was an encounter between two characters that had lusted after each other for years, but were prevented by circumstance from acting on it until now, it would have worked perfectly.
Day One Fixes