The process has been surprisingly painless - thanks to Gabriel Menotti for suggesting Subtitle Workshop - although I'm starting to think we need less dialogue. And definitely fewer people arguing and cutting each other off. And as for sound effects - well, it's the first time I've ever had to Google "vomit onomatopoeia".
Sadly I've seen the script, and heard the audio. there's more dialogue and arguing to come, but at least there's no more vomiting.