First few times I did it the windows were in, but last couple of times they were removed due to a couple of heart attacks during previous excercises (or so they said)
They always give at least one person a lifejacket that has a fired cylinder so you have to inflate orally whilst gasping from the cold water. Marquis De sade! Anyway if you was listening while teecher were talking, best way is to step dry into a liferaft
Presumably, if you have to inflate a gas lifejacket orally, you should remove the gas bottle at the earliest opportunity in case it goes off later? You can't always assume it is empty or permanently faulty.