Dotnet creation fails but construction works in Visual Studio / Slowcheetah

In ASP.NET Core 1.1 (Angular SPA Template) I added slowcheetah to use json transforms on appsettings.json.

In Visual Studio, starting with work on debugging as well as building and publishing zu Azure.

For SPA work, I prefer to use Vs Code. Unfortunately building from there and also from console ( dotnet build

) fails with the error:

C: \ Users \ JohnDoe \ .nuget \ packages \ microsoft.visualstudio.slowcheetah \ 3.0.61 \ assembly \ Microsoft.VisualStudio.SlowCheetah.targets (83.5): error MSB4062: TransformTask cannot be loaded from assembly C: \ Users \ JohnDoe \ .nuget \ packages \ microsoft.visualstudio.slowcheetah \ 3.0.61 \ assemblies .. \ Tools \ Microsoft.VisualStudio.SlowCheetah.dll. Could not load file or assembly 'Microsoft.Build.Utilities.v4.0, Version = 4.0.0.0, Culture = neutral, PublicKeyToken = b03f5f7f11d50a3a'. The system cannot find the file specified. Please confirm that the declaration is correct, that the assembly and all of it dependencies are available and that the task contains a public class that implements Microsoft.Build.Framework.ITask. [D: \ path \ to \ project \ MyProject.csproj]

Possibly a problem with slowcheetah? https://github.com/dotnet/cli/issues/5457 (comment from piotrpMSFT).

Any idea why this fails and how to fix it?

Many thanks,

Martin