Enter the beta access code: CrusaderKings (this may be required by Paradox to see older versions).
Disable and select version 3.0.1.1 from the list. Key Content in v3.0.1.1
Select 3.0.1.1 - Old version 3.0.1.1 from the dropdown menu. Steam will automatically download the legacy files. : Open the GOG Galaxy client. Go to the game page and select Settings (next to Play). Choose Manage installation > Configure .