Noob question: why the pink background for sprite sheets? I bought a set and I can't figure out how to slice it up and make the background transparent. I think I'm missing something.
I think the main idea is that magenta is a colour you're unlikely to use in the sprite so it can be automatically made transparent. It can make colours difficult to judge though if you actually work on the magenta background though. If you need to make the colour transparent you could try using GIMP maybe, it's free and handles transparency quite well in my opinion.
I'm loving Luigi's Mansion lots. It really takes pleasure in the little details like hoovering up coins, which makes the whole thing quite addictive for me. Plus some great atmosphere and lighting effects at times. I'm on the fourth mansion and haven't found it too repetetive so far as each level always opens up new rooms, and each mansion feels significantly different.