If I'm not mistaken, you added lots of artifacts to the "Items" list. Note that "Items" are only for artifacts that can be equipped in the 5 item slots. For example, Sword of Hellfire should be in the "Weapons" list (and it's already there); shields should be in the "Shields" list, etc.
As noted in your TODO, it should check game version before including HOTA-only items. The easiest way is probably putting HOTA items and creatures in their own lists, and add them to the main lists if the savegame is detected to be HOTA.
You can make the changes and submit a new pull request.
Added new creatures, artifacts and items included in the hota unofficial expansion. Added the ability to read hota savegames