they are allways visible. However, ever heard of NCServer ?
It's a protection against wallhack. Its function is:
too only draw the players when you see them. Which means people behind a wall wont show in the demo. So if your demo are from a server with NCServer there is no way to make them visible. Atleast no way that i know off. Thats a sad fact for people that want to make movies and stuff. NCServer removes the recamming possibility.
To get rid of the scorebar:
View -> Demo Information
In the left you will see a column with the title Configstrings. Click statusbar and then the - button. Save the demo and its gone
-Arild