greenfly,
I am happy to get a chance to say Thank you for your great book. I bought it before Christmas and it was my first Linux book. With the book I could learn real Linux from the very first minute. Great!

Back to the issue.

Yes, the whole CD passed the check. Hope, the wrong boot file is not a real problem .

However... in order to make future readers' life a little bit easier.

- I think, that the questionable isolinux.bin boot file is about the initial screen with publisher's data. (O'Reily's hacks URL) So, I have to submit bug report to O'Reilly not to Knoppix?

- testcd seems to be a Knoppix (or higher level) bug. I think it either tests the whole CD's MD5 (not paying attention to files) or is smart enough to decide if the error is significant. In any case the message is confusing in cases like mine.
Do folks have any suggestions before we submit the bug report?