Re: Nui. From the book Ka Lei Haʻaheo: "When nui is used as a [stative] verb, it often means 'there's a lot ofʻ or 'there are many.'" For anyone like me who doesn't know what a stative verb is, it describes the state someone or something is in (e.g., tired, fine, sick, sulky, pretty). In English, these words are called adjectives and are used with am/is/are, etc. to make sentences. In Hawaiian, there are no words like is/am/are so words like māluhiluhi, maikaʻi, ʻōmaʻimaʻi, numa, and nani function as verbs all by themselves. That is probably why DL insists on "There is..." here.
My experience with laulau is pretty minimal, but I guess the word can refer to the finished product (meat wrapped and cooked in leaves) and also to the wrapping itself. The wrapping by itself could be big, but there can also be plenty of laulau/packages of meat, so it would seem that both translations should work.