Hi Mario,
I've played a little bit with the Juicebox export module in the last few days and I think the (extra) help file
C:/ProgramData/photools.com/IMatch5/scripts/system/Plugins/Juicebox/help/help.html
is not correct.
The sentence "or use formula-based categories or Alias categories to reference categories already in your database" is not working as youself described in this post (https://www.photools.com/community/index.php?topic=5362.msg37243#msg37243).
Axel
I have added a sentence to explain that galleries with navigation use directly assigned files only.