GhostScript is a product of artofcode LLC andf Artifex Software Inc. The software is freely available under two separate licenses; we have thoroughly tested Wusage 8.0 together with the freely available GPL (GNU Public License) version. An easy-to-install release with a friendly setup program is available. As of this writing, version 8.61 is supported on Windows (8.62 is not yet available for Windows). You can find a link to it on the wisc.edu Ghostscript pages.
If possible, INSTALL THE PROGRAM IN THE LOCATION THE INSTALLATION PROGRAM SUGGESTS. Otherwise, you will have to take steps to ensure that GhostScript can be found in the PATH environment variable. If this is not 100% clear to you, just accept the default installation location.