I have a new install of Splunk 6.0.3 on Mac OSX 9.2. When I try to use Forwarder management, all I get os a screen that tell me to "Learn More" which tells more all the great stuff you can do, but not how to actually enable Forwarder Management!.
I have trawled through the spunk answer, but most stuff assumed the Forwarder Management is working, and how to try and make the forwarders work.
In addition to MarioM:s answer you should be able to get "forwarder Management" to be activated as well after the first Splunk forwarder "calls home" .
If you were reading the forwarder management overview, the very next topic (Plan a deployment) contains a summary of the steps. Then the topics after that have the details. It sounds as if you might not have configured the apps directories correctly, as MarioM states.