Spatial datasource comes with detailed instructions and there was no problem to install it on my Oracle XE (XE supports spatial functionality). When you start Quickstart kit for the first time, Oracle MapViewer deployment process is completed automatically. You can find instructions in Quickstart readme file about how to open Oracle MapViewer homepage and then according to the tutorial - Learning Oracle Maps by Example (it comes with Oracle MapViewer), configure Oracle Maps settings.
And, finally we have a map, that displays population density by counties:
With sample application comes deployment profile, which you can use if deploying to Oracle Application Server.