I installed Nexpose without incident. During the install I did the initialization. It looked to me like everything went fine. No error messages. When I point my browser to https://localhost:3780 I receive "no data received" from Chrome or "The connection was reset" from Firefox. I did see a problem like this in a thread for Medasploit with no solution. I'd love to see this product in action.
Windows 2012 Server 8 gig of memory, 2 processors.
Thanks,
Tom
Logs are going to be under the install directory, then under ~/nsc/logs/. That should give you some insight into what's going wrong. You could also have security restrictions on your machine blocking Nexpose from running.