Trying to create a starry sky, but it's not working.

For a Space Invaders game, I copied the code from someone's example for how to create a starry sky, such that a bunch of points of light will appear throughout the form and flickering in and out of existence. But when I run the example, nothing happens--the screen just stays completely black.

Here are my classes:

Form1
Game
Constants
Stars

And here's the example I'm copying from.

I changed the name of AnimationTimer to Timer1, but besides that, my code is pretty much identical to his... any idea what's going on?