Hey, guys!
Please take a look at the NCX file below.
NCX File:
It seems like the value for the "dtb:depth" property on NCX heading is being incorrectly set by calibre. The value should be "2", since there are only 2 levels on the TOC. After testing with other books, it looks like calibre always increase the value by 1.
Am I missing something? Or is my assuption incorrect and the value should really be "3" for some reason?