Code4Engineers code does not run

[WAAMLAMB]

Maybe I'm just missing something, but if I download the zip of the Coding for engineers:
https://github.com/LinKayser/Coding4Engineers.git
and unzip in my downloads, it does not work, stating:
The name 'PicoGK' does not exist in the current context

I have the latest version of PicoGK installed from NuGet, 1.7.7.5, and have run the boolean showcase and made a couple simple apps. Just raising awareness.