Small change to documentation
The docs for drawing a map says:
"Draws one of the maps you created in the Maps section on the screen. The first parameter is a string that corresponds to the name of the map to be displayed, for example map1. Then follow the x,y coordinates where to display the map (the map will be centered on these coordinates). Then the width and height of the display."
I think the last sentence would be clearer if it was something like: "Then the width and height in which to display it" - as it is it seems to imply screen.width, screen.height (at least to me!).
The same applies to the explanation of screen.drawSprite.