What did I do?

I used the Play Animation Action which was applied on two objects:
1. The Doors

2. The lights (Blue and Red)

I created the animation so the lights will move backwards and forwards and than I put it on Play automatically.
I also used Play and Stop Sound Actions when pressing the Green or the Red buttons - Relates to the singers and to the crowd.

Once you stand the Green Button the crowd is silent and then the kid/ the woman starts to sing.                 Additionally I added crowd cheering for the kid or the woman so once they start to sing after few sec the crowd starts to cheer for them.

The Scene

The user enters the scene, there are sounds of music and talking in the background, he opens the door (sound of the door opening), he approaches the stage and stand (Trigger Enter) the green button on the left side of the stage - the kid begins to sing, the audience  is silent and after a few seconds applauds to the kid.                                                   The same happens when the woman starts to sing with the piano.