I tried looking on the linked mazes page for a license, the closest thing (in my opinon) was a statement to feel free to reproduce for personal, school, and church use. I figure if I couldn't find the copyright notice, it's probably hard for someone at Kraft to find it too (unless that statement IS the copyright notice).
Does this necessarily exclude a for-profit use, or does that have to be explicitly declared? IANAL, so I'd like to know.
This seems a good example of the actual original meaning of "the exception proves the rule". The fact that he specifically states an intent for it to be free in those cases implies that he does not intend for it to be free more generally.
Coupled with the fact that you automatically have copyright on copyrightable works, and that by default you need license to copy copyrighted works outside fair use and similar exceptions, I think it's clear that if these mazes are copyrightable and if the maze wasn't independently generated (both of which seem more probable than not), then Kraft owes him some money here.
The copyright notice is on every single page of the linked PDF, and every page at krazydad.com has a copyright notice at the bottom. What trouble are you having, exactly?
Additionally, you don't have to provide a copyright notice or any licensing terms for your copyright to be valid an enforceable (with some very special exceptions blah blah).
The maze becomes copyright once it is fixed in tangible form. The license does not include commercial use (which this clearly is), so it is unlicensed.
Does this necessarily exclude a for-profit use, or does that have to be explicitly declared? IANAL, so I'd like to know.