To downpatch to previous game version of BZ you must own the game on Steam. You then need to use the "Depot Downloader" utility to retrieve the game files of the older version. https://github.com/SteamRE/DepotDownloader/releases You will also need .NET runtime https://dotnet.microsoft.com/en-us/download/dotnet/6.0/runtime?cid=getdotnetcore (Select 'Run desktop apps') Run the indicated command in a powershell/command line window, from the directory you have unzipped depotdownloader.dll Substitute username and password where brackets indicate (do not include brackets) The credentials are not stored in any way, just sent as part of the request. Use of 2FA is recommended regardless, you will have to enter a verification code each execution. e.g. for Aug-21 dotnet DepotDownloader.dll -app 848450 -depot 848452 -manifest 3173096341325717512 -username (username) -password (password) -max-servers 20 -max-downloads 20