I never seen the score, or heard the piece, and I highly doubt this is much use to you, but if you eMule KAD search for "Ligeti Desordre", there is a PDF file named: "An Algorithmic Model Of Gyorgy Ligeti's Etude No.1 Desordre"Probably not any use for you in this case, but it makes me intreagued as to what this Etude is all about.
what is it for? Conservatoire, undergraduate, school?
Furthermore, how deep you deal with 20th century analysis trends?
It's a complete different story write a ten-page essay about general considerations and write a cientific, academic oriented, hundredish-page paper. Anyway, kind of good choice to work on. Best to you!
you could easily write a 100 page essay on this piece probably. (...)
Do you really think that? Since you know the analytical and methodological procedures of scientific research, I find that it comes easy. Anyway, it's a lot of work to do that, and another one to produce some purposeful and meaningful academic paper. Maybe "easy" it's not the proper label. OK, "whatever nevemind" (COBAIN, 1991)... Best to you, and Merry Christmas!