I teach a 45 min class also, when it comes to the cooldown, I don't lie back down on the floor, just get the class to march on the spot and breathe in and out lifting the arms up and down a few times, then gradually pick up the original cooldown from the standing position and continue with it. If most of the cooldown is on the ground then just do my own variation of it. I too believe in sticking to the rules, but as long as you bring down the heart rate and stretch the muscles doesn't really matter if you stick strictly to the chorrey or not,as you mentioned safety first.
Happy Stepping!
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