Restart the BA Server. Once the server has restarted, you will see the visualization Example KPI registered in the list of Visualizations when creating an Analyzer report. Create a new report with the custom visualization selected. If you save the report and re-open it, and the visualization settings are remembered. Click on the XML link to view the report XML and visualization state JSON which is helpful in debugging state saving issues:
Test your visualization in the various browsers that will be used. You can add the XML text in the Report Definition dialogue box.
More complex examples included in the Pentaho BA Server noted in Define the Custom Visualization. These examples go beyond this section, including functionality such as server-side printing, lasso'ing, and selections.