29a Mathematical computation, hard stuff (8)
Calculus? I can see 'callus' in there for 'hard stuff' but that leaves two letters unaccounted for.
56a When Westminster quietens, that keeps the wet lot on edge (5,6)
Silly Season. Can't parse the second part of the clue.
1d Fastener joins deer and baby animal up (6)
Buckle? Buck = deer, but what's the baby animal?