Quote: I recommend that you make the background sky image full-screen and center the actual game window to the middle of the screen.There doesn't appear to be an easy way to do that. I was using absolute positioning many times in both JavaScript and CSS.
Quote: Separate it into at least three files.I've been thinking about that, but I have a feeling that then the webhost would cause even more problems than it does now.
Quote: As you progress with your apps, you should look to use automated testing.Sounds good. I made a few errors in the code (the algorithm), some of which caused JavaScript to fall into an infinite loop, that could have been much more easily fixed if I had used automated tests. I also have only recently found how to start the JavaScript debugger in Safari (I was debugging it using the alerts).