This is indeed extremely tricky! The example of "J'ai manqué le train" is a form of transitive usage of the verb ie. the verb taking a direct object "le train". The example "J'ai manqué de le concert ..." is more difficult to explain -- it looks like a transitive usage indirect in the sense of "being deprived of." So without knowledge of the full sentence, it seems to me that the meaning is that something has caused the subject "j" to be "deprived of" the particular concert rather than a general sense of a concert. That's my input, but I think that it would be nice to see a further comment from an expert. Good luck, Jim