OSX Subversion not working / Poor error message

Hey Fritsl -

Can you try the following to see if it resolves the issues

Workaround

  1. Close the editor
  2. Go to ~/Library/Preferences/Unreal Engine/ProjectNameEditor/Mac/ and open SourceControlSettings.ini
  3. Set ExecutableLocation=/Users/Shared/UnrealEngine/4.12/Engine/Binaries/ThirdParty/svn/Mac/bin/svn
  4. Save the file
  5. Open ProjectName in UE4Editor