The bug is similar to http://www.question2answer.org/qa/12163/minor-bug-sub-menu-item-recent-always-appears-selected but this time it is the custom page link.
In my example the custom page is linked to homepage through $QA_CONST_PATH_MAP=array(
OK, I think the solution is as follows. In function qa_navigation_add_page(...) in qa-app-format.php, change:
... to ...
That signifies to a separate part of Q2A that the custom part of the URL should not be matched as a prefix, but rather only if it is the full thing.
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