Breadcrumbs seem to be hopelessly broken. They rely on %META from a %INCLUDE, but want data about the viewed (%BASETOPIC) topic. They can't get it due to a core restriction.
The result is that breadcrumbs point to the web of the skin, not the topic. And it's not clear that they even get the parent right.
Discussion and analysis at http://twiki.org/cgi-bin/view/Support/SID-01208
. Includes patch for skin, but that requires a core change. A prelminary patch for that is provided, but security concerns may make it more involved.
Thanks for reporting. This is a duplicate of Item6438
and was fixed in TWiki-5.0 - read that topic for explanation of early design flaw.