I did encounter these problems while reading Böll's novel (simply 'The Clown' in English), but the biggest hurdle I faced was reading a book with virtually no frame of reference. When reading novels in English, my cultural background usually gives me some kind of insight into the topic and setting, and I often have a good idea of the writer and their background. Without this knowledge, reading can be a little unsettling; it can be difficult to understand why the characters act as they do, and you're not always sure that you understand what the writer is getting at.
Despite all this, I enjoyed the book greatly. The clown of the title, Hans Schnier, has been abandoned by his long-term partner after their marriage discussions broke down because of her Catholic insistence on promises regarding the education of their (future) children. From then on, he descends into an alcohol-fuelled decline, and one night (the length of the book), after returning to Bonn from his latest disastrous performance, he phones family and friends, ostensibly to ask for money, but really to clear the air with people who he (mostly) dislikes.
Many people see the book as an attack on the Catholic church (which Böll denied): it is certainly very critical of both Catholicism and the 'chattering classes' of Bonn's closed-in political world. It is also fiercely against the hypocrisy of those who went with the flow during the Second World War and claimed to be reformed democrats after it. Like the Nazi writer who was briefly censored and then used this to his credit after the end of the war, many of the successful characters in the book have used their positions to their advantage while the honest, generous clown ends up broke and broken begging in front of Bonn station, waiting for his former partner to return from her honeymoon with her new husband.
Much as I love practicing my German, it'll be a relief to return to English for a while (when you start thinking in a second language at night, it's a guarantee of a bad night's sleep!). I'll definitely read another of his books; however, next time I'll have a dictionary and a bottle of paracetomol handy.