When I add a new camera and move it around the Octane view port does not update. I remember some time ago when it worked, but don't know why it doesn't work right now
Seems to work for me. Did you select the second camera in the Octane Viewport? Switching between cameras in Carrara does not switch cameras in the Octane viewport. Also, make sure that 'Free Camera Mode' in the Octane viewport is disabled.