You'll need a Google Service email address and a P12 key file to set the key and email variables below. Go to https://console.developers.google.com/iam-admin and create a service account. Use the options menu to create a P12 key (not a JSON key). Then log in to analytics.google.com and use ADMIN/User Management to add your service email address with Read & Analyze permissions.
ganalytics.csproj and packages.config target .Net Framework 4. Look out for bin/Debug/ganalytics.exe.config: it fixes the System.Net.Http.Primitives reference version error. You'll need to do a nuget install packages.config in the Packages subdirectory. Then build and run! Good luck!
Adapted from Logan G's excellent stackoverflow answer.