I'm guessing this means "a little bit of self-praise has never hurt anybody yet". That fits the context, anyway...
Had to try to deconstruct it myself - I doubt if this word (I use the term loosely) is in any dictionary on the planet, though whether it's in the lingua franca I have no way of knowing (at least, not without asking someone, which I am loathe to do. It's one thing if the info is volunteered...). This is why German is fun!
Actually, now that I am thinking about it, I have to admit, I often use the same kind of construction - I just separate the words with hyphens. It's the exact same kind of mashing-words-together-to-indicate-that-t
Hypercompound word. Ultracompound word. Megamaxisuperextremocompound word. Hmmm...