Really hard to read Kafka, frankly, but I love the major stories of his ("The Trial", "Metamorphosis", etc) and his many short stories so much that I've been trying to learn German (and French, though not necessarily at the same time) over the last year and a half. What I've learned is that I can quite easily pick up meaning and basically understand German when I hear it, about the same when I read it, but I still can't speak it at all - at least not conversationally. I could get around Germany in an emergency if I ran into any Germans that don't actually speak English, which I understand to be a rare occurrence, but that's not really the point.

I think I've discovered I need to be way, way more fluent in German than I expected to be able to read and enjoy (such as you can) Kafka, and I've decided I probably need to live abroad for several years to achieve this goal. Of course, it would be kind of crazy (but not necessarily Kafkaesque) to live in a foreign country for several years just so you could understand one of its authors in his original language. German was of course not his real original language, but you get my point.