so I am DMing ToA and the party has found and joined Artus Cimber and Dragonbait and here is the big problem, Artus has 0 of his spells from his ring or dagger on the sheet and doesn't even have the spellcasting feature on his block, his spells should be included in his statblock for ease of casting them or at least little links in the description of his items, I am currently adding them manually
Ok, to confirm, the problem is with Artus Cimber? (You also mentioned Dragonbait.)
While I agree that spells on the spellsheet might be a good idea, these are not spells from a class but from an item. Based on other adventures I have seen spells from magic items may, or may not, wind up on spell sheets.
With that said, this may be worth bringing up with the Devs. I suggest sending some product feedback to the Devs via the Help Center as the forums are primarily for users helping users.
Edit: One more question, when you say 'manually' you mean drag an drop from the compendium I hope? Not typing them out manually?
I would start by dragging spells from the compendium and then alter them with the desired changes rather than typing them out from scratch.
As for other statblock differences, that isn't a "Roll20 module" issue if the statblock is the same in the printed book. It may be just how they were written up in the book.