Two questions for the hivemind.

A) Under what circumstances does Spell Striking trigger. I'm finding it slightly hard to tell. Is it just crits or?
B) Spell Binding items, especially as a backup weapon, will frequently not display the cast button for me even when the correct weapon is equipped, or often not restore uses after resting. Does anyone know the exact shape of this bug - when and why these bugs will occur - so as to work around it?

As to binding I found out sadly you have to have the item not only equipped when you rest, but also if its a shield or weapon the set has to be selected. If you still have no fresh uses after rest quit your game completely and reload the autosave before resting.

As to striking I know only about shod in faith boots they trigger only on crits.