Building Unreal Tournament Editor from source

Basically I followed the README file available on the GitHub but instead of downloading the zip file I cloned the repo and checked out the release branch (commit 36890a812001f3ff8bdf67269af1e165cddae5dc).

First I had this problem:

3>  Parsing headers for UnrealTournamentEditor
3>    Running UnrealHeaderTool "C:\Users\bartl\Documents\Unreal Projects\UnrealTournament\UnrealTournament\UnrealTournament.uproject" "C:\Users\bartl\Documents\Unreal Projects\UnrealTournament\UnrealTournament\Intermediate\Build\Win64\UnrealTournamentEditor\Development\UnrealTournamentEditor.uhtmanifest" -LogCmds="loginit warning, logexit warning, logdatabase error" -Unattended -WarningsAsErrors
3>EXEC : error : UnrealHeaderTool failed for target 'UnrealTournamentEditor' (platform: Win64, module info: C:\Users\bartl\Documents\Unreal Projects\UnrealTournament\UnrealTournament\Intermediate\Build\Win64\UnrealTournamentEditor\Development\UnrealTournamentEditor.uhtmanifest, exit code: CrashOrAssert (3)).
3>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.MakeFile.Targets(41,5): error MSB3073: The command "..\..\Build\BatchFiles\Build.bat UnrealTournamentEditor Win64 Development -waitmutex" exited with code 3.

and later UE4Editor-UnrealTournament.lib could not be built, no reason stated.

I tried the whole procedure multiple times, deleting temporary folders and running Visual Studio explicitly as admin. Finally it compiled successfully but I don’t know what made it work.

Unreal Tournamet Editor, Outpost 23