Not that I recall.

He mentionned it in Lector in Fabula (or at least in the same book this essay was from, in the edition I have), and IRRC in a late 90s essay I only know as Six Promenades dans les bois du roman, and again in his recent essay on translation, Eco elaborates on the idea that attempting to abridge Monte Cristo, cut down all its disgressions and redundancies would deprieve it of devices meant to slow things down, intrisically necessary to the very concept of revenge, following the saying that it's a dish best eaten cold.

He's mentionned Monte Cristo in several interviews over the years, though essentially he reprises the same core ideas from his original essay each time : "One of the most fascinating novel of all times/one of the most badly written novel of all literatures and times". He discussed it in one of his "three musketeers" conferences with Salman Rushdie and Vargas Llosa too - they debated his claim that it was a "bad novel" for a while.

At the time of Foucault's Pendulum, he had spoken of its influence (and in a more general way, Dumas's) on that novel, thought that's so long ago I don't remember what he said about that.