I made a tutorial with a list of tricks etc that I learnt. If you look at section 7 there is an explanation about which corona versions have which problems, and how to support < 2.2 and arm6. This should give you an idea of how much of a mess it is!
If you want to only target Android there are better options - check out andengine. If you want to target iOS its perfect. If you want to target both, then its still the best option but only by a slim margin. Just stick to the versions I listed in my doc.