Install Nuget package from network cake drive

We have a few mapped nuget packages that I would like to use in my Cake script. The absolute path to the drive looks something like this:

\\ MyDrive \ NuGet \ Packages \ mypackage.nupkg

Is there a way to reference this package using preprocessor directives as described here: http://cakebuild.net/docs/fundamentals/preprocessor-directives#tool-directive

If not, how can I do this without preprocessing directives? Thank you.