Glad the shocker at 49a was raised, I couldn't believe that was the answer but it couldn't be anything else.
43a also annoying, shouldn't the word order of the clue be: Endless video game with associate to a negligible degree? I also agree with loge that the wording of 6a seems wrong.
47d Ate together with doctor, being invited in (6)
Is this messed? If so, what's 'esse'?
28a Kid to remove quickly on being constrained by age (4,1,4,3,2)
Pull a fast one on?
I can't see the age.