i wanted to add the shield attribute to my new character, unfortunately i can only select the health attribute again, it does not give me the option to select the shield attribute like in the example character.
I believe the issue is that you need to add that Attribute in the AttributeManager script attached to your main Player:
... then you'll have to fill in the info in the popout once you've created it and I think it shows up then.
I had to add a generic "protection" attribute to this for a slider and it worked like a charm. As you can see from the CharacterHealth script, I haven't renamed the field yet (it's still "shield"), but to get that to display right you'd have to change something in the Health script CharacterHealth inherits from.