I faced same issue. I was pressing on "Find..." button and there searching for the computer, that always gave me "Found 0 connection". It looks like a VS2012 bug.
However when I've entered computer name (IP address also worked for me) and port in the "Qualifier" field and then pressed "Refresh" button far below - only then the connection was established and the list of processes was displayed.
The format of the text in the "Qualifier" field was COMPUTER-NAME:PORT
(e.g. WIN2012-TEST:4016
) as well as IP-ADDRESS:PORT
(e.g. 192.168.1.1:4016
), both worked. The port was the one that is displayed in the Tools -> Options of the Remote Debugging Monitor running on the target machine.