You will need to manually configure the PC connected to the Leap Motion controller to accept remote connections (this is a change in the service as of version 1.2),
To do this, find your Leap Motion config.json file and add:
"websockets_allow_remote": true
using correct json syntax.
The file is stored in the following location:
Linux: ~/.Leap\ Motion/config.json
Mac: ~/Library/Application\ Support/Leap\ Motion/config.json
Windows: %AppData%\Leap Motion\config.json
Be careful on Windows that you are editing the config file for the user account that the service runs under (there can be more than one AppData folder, I believe).