I created a template for the Vocaloid wiki that would line up the Japanese lyrics with the Romaji. It works when the lyrics are 'about even' on each side, but when either the Japanese or the Romaji contains the longer word count the whole lyric set gets misaligned.
I tried to see if the line height was the problem, but it doesn't seem to effect it much.
Currently the fix for odd lyric balance is to use a table that gives each set of lines its own cell each row. The thing is I created the template for contributors who don't know how to use tables. It is also rather tedious to do.
The Oasis skin just doesn't work very well for it. I tested on the Sandbox and adjusted it each time to see if I could match the 'table cell/row' method. I am aware of the option to simply 'stack' the two sets of lyrics on top of one another, but curerntly the side by side view is the most favored.