-Light Guardian is used in ex+alpha, where the song titles are listed at the start of the battle in English ala Soulcalibur, even in the Japanese version. Unlike the other two tracks in question, the name is exactly the same between EX and EX plus alpha, so I take Light Guardian as the official name, especially sense it sticks to the same naming format. [i.e. Strange Sunset, Heat Wind, Rising Dragoon, Spinning Bird]
http://www.youtube.com/watch?v=TTeTWNBsze8 at 2:42 (PAL)
http://www.youtube.com/watch?v=zczsB3ayZCg (JPN)
-The original EX is 夜桜満開 (Yozakura Mankai). Sakura Mankai (桜満開) lacks the first symbol. It also makes sense that Yozakura Mankai isn't as loud as Sakura Mankai, as it suggests that Yozakura sounds like night and Sakura sounds like day, despite the fact that the background is unchanged.
http://www.kamus.com/jap-eng/%E5%A4%9C%E6%A1%9C - Yozakura
http://www.kamus.com/jap-eng/%E6%A1%9C - Sakura
http://www.youtube.com/watch?v=Y3VT0vDEmjg - Yozakura Mankai (EX)
http://www.youtube.com/watch?v=kjhP0takPAs - Sakura Mankai (EX plus alpha)
-Tenkyaku Maiuta (天脚舞歌) (different from Spinning Bird) is interesting. The Tenkyaku part goes without saying, but for Maiuta, 舞 = mai [dance], and 歌 = uta [song].
http://www.google.com/search?hl=&q=%...US361&ie=UTF-8 - "舞歌 maiuta" Google search
Check the first and fourth (non-vgmdb) results for this page. Maiuta is definitely a romanization of 舞歌, especially since the sites they come from are Japanese. I don't know where Buka came from, considering buka = subordinate person. So what do you think sounds right: "Heavenly Leg Dance Song" or "Heavenly Leg Subordinate?" Your call.
http://www.kamus.com/jap-eng/buka - Buka
http://www.google.com/search?hl=&q=%...46cf3aa56f846d - "舞歌 buka" Google search