Sprites are not rendered to the buffer until you use render() or sync(). If you use drawSprite() it will render the sprite in its current position to the buffer. There are a few ways this combination can be used.
Render()
DrawSprite()
Sync()
... To draw specific sprites like my draw commands on top of the current scene.
drawSprite()
GetImage()
ClearScreen()
... To draw a set of sprites, get a combined image and continue without it being visible in your game.
I would read up the help files as they helped me understand the best order to do certain operations.