“Corrlá” is a compound of “corr-” (“an odd, some”) and “lá” (“day”), thus meaning “an odd day”, “some day”. Same thing with “leathscór” which means “half a score” or “ten” (“leath” + “scór”). As for you last question, it’s two separate words, “nach” (“isn’t it?”) and “iomaí” (“many”). So the entire title would translate something like “Aren’t there many twists in life?”