Question 1: Manual approach 

A:5C  N:5F      ____ EUROS NINNIES SNEEZE FOX SISSIES FUROR SNIFF FIX
B:5F  O:20    FLUBBED CUCUMBER RENT SNIP CURRY SINEW WORKOUT LOCKUP Y
C:7C  P:7C    MUCK UP COMFY RD YUCKY ROCOCO UP PERK HOW X TOLD CROP M
D:7C  Q:20    DODO UM DEDUCE COMFY DUKEDOM RUMORED ROW HOT LUCKY UM D
E:5F  R:20    M MINICISE Q EGG MUD DECOY MINED CENSOR A V LOUD DESCRY
F:20  S:5F    RAISING KOPECK PIP RHINESPENBINGESNEEP ROAST O RABIESTO
G:7C  T:2F
H:5C  U:20
I:5F  W:5C    S = 0x5F = _
J:2F  X:20
K:20  Y:7C
L:2F  Z:20
M:7C