Null (0) - What is it for?

In cave story, there is a map called Null, with the filename 0. You never go to it in-game(Though thats not suprising, considering its just black with no real tileset), but it has a bunch of Null/Nothing entities in one corner of the map, with events on them, and the script for the map has these event's showing the credit illustrations. What is it for? Is it actually used during the credits?

 

Is it actually used during the credits?

yes

 

yes

I also always wondered what this was, it makes sense that its used in the credits. huh.

 

I figured this would be obvious but you are staring at that map for 90% of the credits.

 

The illustrations scroll, not the stage! It is, indeed, the credits...