Access internal Sunstone from external site

Hello, we currently have a OpenNebula up and running internally, and would now like to be able to access it from one of our external web sites that runs apache2.

Here is setup:
external site is and has access to internal opennebula/sunstone
we would like to link to it as something like

using apache2 mod_proxy and mod_proxy_http we are able to get to the login page, although it doesn’t fully render. Then when we log in the ‘sinatra doesn’t know this ditty.’ message.

Here is apache2 config file:
<VirtualHost *:80>

    ServerAdmin webmaster@localhost
    DocumentRoot /var/www/test
    ProxyRequests Off

<Proxy *>
Order deny,allow
Allow from all

    ProxyPass /nebula/ http://internalip:9869
    ProxyPassReverse /nebula/ http://internalip:9869

Any ideas, suggestions, thoughts on how to fully enable access to our internal sunstone from external site?

Thanks in advance