Ligeti Etudes are incredibly difficult. They should not be attempted except with a teacher and most likely only by professionals.
Dnephi said it all. I must add that only after mastering some Chopin, Liszt and Scriabin studies one should attempt to play Ligeti's. Best!
You make it sound like some dangerous explosive that will ruin my playing if I attempt to play it It can't be _that_ hard, can it? Afterall, there are only so many notes one can fit on a staff...