Then, click the Download option for the steam_api.dll file. When you’ve downloaded that file, you’ll need to extract its ZIP archive and move the steam_api.dll file into the C:\Windows\System32 folder ...

A powerful Steam API proxy that functions as a "Man-in-the-Middle" between a game and the Steam Client. It forwards API calls to the real Steam library while overriding the AppID to 480 (Spacewar), ...