Errors when regenerating *.g.cs files

[Minus-Cortex]

To reproduce, use the plugin to generate the view-models for the test project Xamarin.Sample.
Then, implement the required methods into the main file of each view-model.
With Visual Studio, use the contextual menu Rebuild.
The generation fails because all the *.g.cs files are inexistant.

Version of Visual Studio : 2017
Version of MSBuild : 15