I’d double check to make sure you properly setup ‘OnlineSubsystemSteam’ properly, and have the correct code and SteamDevAppId in your ‘DefaultEngine.ini’ file. There may be other issues in the code somewhere, but in the log it shows it’s crashing after trying to load the OnlineSubsystemSteam plugin, so once that’s fixed you can try packaging again and see if that fixes it or if there’s another error.