OP here.
First pic is the one book I've read of him. It's a bit like Democracy - The God that Failed in economically illiterate, but with some fascinating ideas and historical facts to make up for that. In fact, I stumbled over it thanks to the frequent citations Hoppe made of it in his work. Among other things, I learned the crucial differences between the Protestant and the Catholic mindset from it.
Second pic is what I'm reading now. Sadly, it cannot measure up to von Kuehnelt-Leddihns later work. What's good in it is great, but there's so much trash thrown around, it's hardly funny anymore. His criticism of capitalism and the "bourgeoisie" is superficial and not really worth reading, he's way too sentimental and nostalgic, and too sympathetic towards socialist thinkers and ideologies. Still a book worth picking up, but it requires a very critical eye and some patience, even more so than Liberty or Equality.
The file is one of his essays, if you want to get a taste of his work. What it might miss, to a certain degree, is von Kuehnelt-Leddihns impressive insight into the human psychology. His descriptions about that almost read like poetry, really.