Congratulations Slaney. I trust you didn't sample each one as you wrote it down?
It's nice that another one of the group has won. Here's wishing us all luck in trying to be the next winner.
Yes, pity about 40 and 41a. 41 could be a proof-reading problem, but I don't see how 40 can be other than the setter's error. I agree that one of the unclued lights is hard.
Helveticus,
It's not the over-regulation case; remember the proper noun in the preamble and place your faith in searching through the possiblities for the fifth letter.