I recently aquired a beogram 5000 and replaced the light bulb that illuminates the turntable.  I notice that when the lid is closed, the light goes off.  When I open the lid about an inch or more, the light goes on.  Is there something wrong with my thinking to assume that the light is supposed to stay on when the record is playing or is it a utility light to help you when you're changing the record or adjusting the tone arm?  anybody?

It is , as you describe it, a utility light. It only switches on when the lid is open.

The stylus can operate, quite happily, in the dark!