Multisite activation on an Amazon EC2 instance

Hey, I have just installed a Bitnami HVM Wordpress Multisite on an AWS EC2 instance. To enable the multisite functionality I did update the wp-config.php file and the .htacces one as shown in the instructions (code with the Bitnami distro for wp-config.php and .htacces comes with the site and appears on the dashboard).
Also, the EC2 instance is set to an elastic IP (static IP) and because I don't have wildcard subdomains possible with this configuration I set 'SUBDOMAIN_INSTALL', false in order to have separate URLs for the new sites. PRO sites plugin is enabled.
SO: I create a new site and:
a) When I access it to view I get only the HTML page with no CSS !!! (just simple HTML page with links).
b) Plus when I try to access the dashboard of the newly created site I get to "page isn’t working" page (dashboard URL does not work).
What am I missing?