I have the new regular THE ROBE dvd which I enjoy very much. I like the movie, I had even bought a video of it several years ago....I also got DEMETRIUS AND THE GLADIATORS, both were shown on NBC'S SATURDAY NIGHT AT THE MOVIES, probably during the first season.
"Demetrius" was shown, but not "The Robe." As Saturday Night at the Movies was in the second half of its second season (1962-63), "The Robe" was having its first theatrical re-release (1963).
ABC bought the rights from Fox to do annual Easter airings of "The Robe" starting in 1968. They paid quite a tidy sum for it, too. After a few years, Fox sold the rights for TV packages of "The Robe" and ABC switched its Easter offering to "The Ten Commandments" which continues to this day.
Happily enough, the very first movie shown on Saturday Night at the Movies was the very first movie COMPLETED in CinemaScope (albeit the second one to be released to theaters): "How to Marry A Millionaire".