I'm at the "add global search" stage of working on my new #NortonGuide reader; and it's thrown up some issues with corrupted or badly-written guides. So NGDB v0.10.0 is out and it's much more defensive. https://github.com/davep/ngdb.py/releases/tag/v0.10.0
I also wrote a tool to scan every guide I have to hand to look for any issues: https://github.com/davep/ngdb.py/blob/main/.comprehensive_test/read_all_known_guides