I made one a few months ago, Bb had said it was the one pudding his mum used to make and he loved it, but the main reason was it doesn't have any milk or cream so was ok for youngest!
The meringue was good, but I seem to remember it has to be done at the last minute.
I used to make so many puddings, I hardly ever do proper ones now, so not much help
Oh unless you're any good at profiteroles, they'll keep a good few hours without spoiling, and you can make the jug of chocolate sauce ahead too. I didn't know they were meant to be tricky so never had any trouble with them