Outdated Reference in ...CodeGeneration.Design" Version="2.0.0-preview2-final"

[RandyBuchholz]

There was a compatibility error with Microsoft.Composition. This is being addressed https://github.com/dotnet/corefx/issues/18452.

CodeGeneration.Design is still referencing the old version and gives:
Package 'Microsoft.Composition 1.0.27' was restored using '.NETFramework,Version=v4.6.1' instead the project target framework...

The correct version is 1.0.31.

[RandyBuchholz]

Workaround. For a new project this seems to get things right.
In VS2017-3

1. Create a new MVC project. It will bring in three references. AspNetCore.All, EntityFrameworkCore.Tools, CodeGeneration.Design. There will be a warning on Design.
2. Remove CodeGeneration.Design from your project file.
3. In PackageManager add Microsoft.Composition 1.0.31
4. In PackageManager add CodeGeneration.Design

The subs to Design are different now and everything seems to work