An audio production of this scene will differ from a stage production of the same scene in that the listeners would have to visualize the dress and movements of Fritz and Frank. An audio production primarily appeals to the listener's hearing. It conveys the message of the scene by a change of tone or the use of objects to mimic a sound.
You make a conclusion based on what you read or whatever.
Understand the plot and know the characters well. You should be able to portray the play like a drama in your mind.
Egomania is basically intolerably self-centred. In a more technical sense, it's an obsession -- an obsessive preoccupation with one's own self, usually in the form of following own impulses and have delusions of grandeur.
Megalomania is a rather loose term, and usually means have delusional fantasies of omnipotence (having unlimited or very great power, whatever 'power' might mean to that person). Interestingly, megalomania was the standard term for narcissistic personality disorder before the 1960s (so far as I recall from my psychology degree over 30 years ago).
