"> Our GOG and Humble Sunless Sea builds are DRM free, the Steam versions
> contain DRM as most steam games do.
> The DRM check is failing because the steam_appid.txt file is present and the
> game is being closed as a result.
> All the best,
> [Name Removed]
> Failbetter Games"
In short, i'd ported my copy of Sunless Sea to a USB stick (as I always did then) and blocked it communicating with steam (via ZoneAlarm). The reply was #13 of 15, and I've still never yet had a reply to my question of when they added the DRM (the game being DRM free on all platforms was the reason a bunch of us bought the "lifetime" package on steam long prior to its release on GOG).
Actually the wiki page doesn't claim that the game runs as is.
The wiki page states "Delete or rename steam_api.dll in the game's directory."
Also, that person's comment indirectly says that deleting or tinkering with steam_appid.txt might make the game start even without Steam.
Are you saying that doing all that still doesn't allow the game to start?