I know one: The title screen music is actually an instrumental version of a Chinese song: 每天愛你多一些, by Jacky Cheung - a very famous singer. You can look up the English translation if you like.
EDIT:
2. It is played during the emotional conversation between Artemi and Sidd during the ring fight intermission: Slow instrumental version of 富士山下 by Eason Chan.
3. 情非得已 - by Harlem Yu - played during confrontation between Cole and Artemi when hiding from mind-controlling mage.