Since NaSt3DGP is developed mainly on Unix-based systems the support for Windows is very rudimentary. We only provide a simple Makefile for the MS VC5 compiler which can be used with nmake. The file Makefile.VC5 is included in the distribution in the directory NaSt3DGP/src.
Another way to use NaSt3DGP on Windows machines is to install a Cygwin-Environment. You can download Cygwin for free from http://www.cygwin.com. If you use it, simply follow the build process as described in the Unix-section.