Laminitus! some questions?

I'm new to laminitus and I've just sat and read loads of stuff but still confused. A horse at our place came down with lami yesterday, laid all day in field then was brought up at night, walked like a german trooper across the field but appeared ok on concrete. Can you answer these questions, please! The owner gives her a slice of bread everyday as a treat and did last night, is this ok? although she's been out 24/7 for over 2 wks he gave her a bucket feed of coolmix and speedibeet, she hardly ever gets exercised so would this elevate the condition? I know carrots are bad but I've heard apples are ok is this the case? Should we let her graze for short periods even though she seemed very stiff and sore yesterday or should we wait till she gets a bit better? Thank you!