I've been searching for information on track 21. According to several sources, it's a chinese cover of the original japanese sung and composed by Shinji Tanimura (谷村新司).
This
page contains information about the original version, but I couldn't find any sources for the cover version, so I don't know who is the singer of the chinese version (the one included in the soundtrack). If someone has any kind of information about this, please don't hesitate to share it.