Installed it on my MacBook Air with OSX 10.10.4 Takes to while to start running. Finally shows a list of 'instruments' and only one of them can be selected, sho

Installed it on my MacBook Air with OSX 10.10.4 Takes to while to start running. Finally shows a list of 'instruments' and only one of them can be selected, showing a 'record' and 'run'. Clicking run turns the whole screen black. The webcam is on, but nothing is visible or can be done. Not sure how it should work otherwise. Have been waving a lot :-) Maybe it is just a hoax and now the recording of my efforts is published online ;-) Some secret service might be wondering what sign language I am using...