Firstly, ensure your JeVois is running the most recent image version. Inventor is not guaranteed to work with old versions of the JeVois system.
Another caveat about Inventor that is slightly unintuitive is that it does not refresh the available cameras automatically. One must click 'cancel' in the camera selection dialogue to force a refresh. Once the orange LED on the JeVois turns on, Inventor should be able to detect it.