Is there a way to enable a Persistent Spell hot bar for my equipped Spell book? Right now, I can only see the spell hot bar if I have an item able to cast spell book spells in my hand, even if the spell hot bar is supposed to be focused. Am I missing a config option?

Hello!

It is not possible, since Spell Hotbar content is also influenced by what item the player is holding.

Would it be possible to add a rule to spell hotbar behavior where IF a spellbook is present in the Trinket slot, the hotbar is shown with the spellbook spells. Then if a player is holding an item that adds additional casting abilities, those are simply added on to the spell hotbar while the item is present in player’s hands

What game version are you using?
On the 1.20.1 version there is no more hotbar swapping.

Oh I see. I am running the 1.19.2 version. By no more hot bar swapping, what do you mean by that?

1.19.2 versions are no longer being developed.
I recommend updating to 1.20.1, where Spell Engine offers keybindings to control individual spells.

Do you plan to continue supporting the spell hot bar or is that effectively removed?