I've finally figured out how to write Vocaloid lyrics reasonably quickly:
- lay out as many notes as there are syllabes for one or two sentences
- right-click the first note, choose the next to last option
- Write your sentence as engrish syllabes, each one separated by spaces. For example, 'i ro ru do mi tu i zo do mi ci ru' for "He lured me to his domicile".
There is a dictionary (ALT+L then C) but I've not figured out how the hell it really works yet.