Thing is, there is absolutely no copy protection for Minecraft to bypass, and that is also NOT part of DMCA, that is part of other very US specific Laws. And there is the thing about you being allowed to own ROM files for Games you already bought. As long as you dont redistribute them you are perfectly fine, legally speaking.
You are not allowed to share how you broke the copy protection, but you are allowed to break it for personal use.
It is very important that personal use is always fine for yourself, redistribution is not. Especially if you bought the Product. Which also includes stuff like DVDs.