SpiffGIS is currently nothing more than a GeoTools LAB build on the tutorials here: http://docs.geotools.org. Its implimented using the Netbeans Platform and build using maven.

Add the following proxy repository to your Nexus proxy if your using one:

Repository ID: osgeo Repository Name: Open Source Geospatial Foundation Repository Repository Type: proxy Repository Policy: Release Repository Format: maven2 Contained in groups: Public Repositories Remote URL: http://download.osgeo.org/webdav/geotools/