Generally, no. These forms are the same. But you can use special words (so, actually, you can remove the confusion) - you can use the word прямо сейчас (right now) if you want to emphasize that she is not smoking right now.
Of course! Firstly, if you are not using any words, the native speaker would think that the mother doesn't smoke at all. But if there are some misunderstandings, you can add such words: никогда (Мама никогда не курит - Mom never smokes), вообще - generally, at all (Мама вообще не курит - Mom doesn't smoke at all).
And again six repetitions in a row. That isn't learning, it is a waste of time!
I've noticed that the pronunciation is wrong on a few of these Russian lessons. They need to fix the lady's voice from all those years of smoking, am I right?