There are lockers and an actual check i believe at the middle east entrance first floor.
For your luggage, if you go to the front desk or bellstand you can check luggage with them. They keep all luggage in a secure and locked location. They give you a ticket stub, and thats how they find your luggage. Theres also a concierge louge if youre a Marriott's Rewards Member.
I dont believe so, but they do have lockers for personal use
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