I've got a little further with this through a bit more testing and configuring. I noticed that the properties that HWI uses are actually not being set or at least are not set correctly. So I set them in the Ambari UI. I also noticed on the HWI home page that it requires Ant, so I installed ant. To set the properties in the Ambari UI, on the services page:
1 - Stop Hive
2 - go to the Hive configuration tab
3 - under the advanced area add these three properties:
*hive.hwi.listen.host = 0.0.0.0
*hive.hwi.listen.port = 9999
*hive.hwi.war.file = /lib/hive-hwi-0.11.1.3.0.0-107.jar
4 - restart the Hive service
Then in the terminal set the linux environment variable ANT_LIB = = the path to the lib directory inside your ant installation.
Then launch HWI with 'nohup hive --service hwi &'
that got me to a point where I could see the directory listing, but not pass any hive commands. I will continue to play around to see if I can get the full HWI up.