SteamUserID

SteamUserID

Every steam account has a unique SteamUserID. In the steam installation the 32-bit ID is usually the only directory with numbers (!=0) in ~/.steam/root/userdata/. If there are multiple dirs you likely use multiple steam users with your computer account.

steamtinkerlaunch by default used the first directory found, which works for most users, because most do only have 1 steamuser. This default can be overridden by simply adding (manually) STEAMUSERID="YOURID" (replace YOURID with your id here :)) to the Global Config

(the 64-bit ID can be easily calculated from the 32-bit one, but is not used in steamtinkerlaunch)