I got the book as a gift for someone who's totally new to programming, and I kinda skimmed it before wrapping, so my impressions are just that -- impressions.
That said, it seems like a) the book could get a complete beginner pretty much up to speed with the essential concepts of BASIC, DB or DBPro flavor, and b) the authors spend hundreds of pages covering those basics with extreme verbosity, then notice the book's already three inches thick and say "Oh yeah, you can also do some stuff in 3D... see the command descriptions that come with Dark Basic for more on this."
It would have been better to describe variables, looping, arrays, etc., more briefly then give that same level of attention to individual 3D commands, IMHO.