Currently useful manifests are as follows:

• 9204909284884878595 - 1.0.0.6 - Old moon patch
• 4163843425391060582 - 1.1.1.2 - Disso bug patch
• 9058106608706845920 - 1.2.4.4 - Devotion Update
• 5418745512668761974 - 1.3.6 - Phase 1 SotS

Downpatching through steam:

This method works as of the time of writing, but Steam has disabled it in the past.

1. Open the steam console by pressing Win+R and typing in steam://open/console
2. In the console type in download_depot 632360 632361 manifest
3. There will be no indication of the download progressing in the console, but it will say when it's done. Be patient. The files will be downloaded to path/to/steam/steamapps/content/app_632360

Downpatching through DepotDownloader

This is a 3rd party app you'll need to put your steam account details into. It's the best option in case Steam breaks downpatching through their app.

1. Get DepotDownloader here https://github.com/SteamRE/DepotDownloader/releases
2. Unpack it somewhere and then open cmd, easiest done by searching for "cmd" in Windows.
3. in cmd, go to the place where you unpacked DepotDownloader. You can navigate cmd by using the cd destination command, or do cd .. to go back a level. To change the drive you're in simply type in the drive letter followed by a colon like E:.
4. Type in dotnet DepotDownloader.dll -app 632360 -depot 632361 -manifest manifest -username your_steam_username -password your_steam_password The files will be downloaded to the directory where you unpacked DepotDownloader

If you get an error saying "'dotnet' is not recognized as the name of a cmdlet", make sure you have .NET Core installed. You can get it here: https://dotnet.microsoft.com/download/dotnet/current