Open the 'gzdoom-(YourPCUserNameHere).ini' and scroll down to where you see.
Run the game once to have the gzdoom-(YourPCUserNameHere).ini created automatically.
Copy/Move "Project_Brutality-master.pk3 over to the ' /base' folder located within the doom steam folder.
Once downloaded, rename "Project_Brutality-master.zip to "Project_Brutality-master.pk3 (it's important that you have File Name Extensions checked in File Explorer, click the Ribbon dropdown > Go To View tab > Under Show/hide section > Make sure the "File Name Extentions" checkbox is enabled/checked).
Click on the Green Button that is labeled as "Code".
This spawned even more adaptations, due to fans porting the code to an array of other devices. Originally released for PC DOS, the games were later ported to a number of other platforms.
Go to the GitHub Repository for Project Brutality 3.0 in the "Getting Started" Section The franchise was followed up by Doom II: Hell on Earth (1994), Master Levels for Doom II (1995), and Final Doom (1996).
Delete dosbox.exe, then rename gzdoom.exe to dosbox.exe.
Copy all files from the GZDoom zip folder to your Steam Doom /base folder.
That's ok, just apply the following steps below in that folder - as if you are treating it like it's a /base folder)
Open /base folder (if you are in the Master Levels of Doom folder you will not see a /base folder.
Open the GZDoom 7zip file you downloaded.
Install Doom then locate the folder in explorer ( Steam/steamapps/common/(Doom).
Download the latest version of GZDoom (currently 4.5.0).
Download the latest version of Project Brutality (currently 3.0).