I spun. I prayed. Game does what it says on the box. I solid little slot machine game. Well done.
You may want to look into your sprites disappearing. At some point after I bought a drink, this happened to me. Either some of the images are not getting drawn, or their getting drawn before the background:
[Edit: I'm noticing that the image I pasted isn't showing up when I save the message. If you don't see it, you'll just have to trust me :) ]