1. you may want to check this software for transition, it has OSX version.
https://www.mobileread.com/forums/showthread.php?t=11123
2. I am not a fan of manga, but many other guys I know bought 505 only for manga reading. Comic to LRF is more like put multi images in one LRF assembly, thus I don't think it has anything to do with specific language.
3. You would find a lot of manga in Chinese here, if you can read Chinese. Meanwhile, you can find "Previews" about how manga looks like in 505.
http://www.hi-pda.com/forum/viewthre...extra=page%3D1