The directions need to be followed exactly or there will be problems in the code.
If you have problems, you should use firefox, and install the FireBug extension.
Once the error is known, whatever problem you are having can be pointed out.
There is a zip download of the files changed by other people floating around, but
I would not recommend it because google will likely go after those people; the code
itself is copyrighted and should not be posted anywhere.
Some people also put it up on github; but they are still using a very messy index.htm
at the moment, rather than the stripped down code I showed above.