Think it's complete, but cannot rationalise cryptic elements of four clues.
31A Suddenly faint, about to live in America (8) U-A-A-E- Presumably UNAWARES. ie WAN reversed in US. But what has ARE got to do with 'about to live'?
49A Taking off skirt, essentially, it's part of procreation (9) I-I-A-I-G Presumably IMITATING. MATING is in there, leaving I-IT and 'skirt, essentially, it's' unaccounted for.
50D Uncovered surface that's arched a shade (5) A-B-R Presumably ARBOR, but why?
52D Country where open season's beginning with uprising (5) S-R-A Presumably SYRIA, but why?