Dawson Casting: Somewhat. Peter Cushing was 44 when he starred in this film. The beginning of the film suggests that Victor first began his tutleage when was still young enough for Paul to initially mistake Victor for the young son of the Baron, rather than the Baron himself. Young Victor is played by a much younger actor than Cushing and the lines suggest that he is still in his teens at the time. Assuming that about 10 years passes between this and the present (and given the barely noticeable aging of Paul), the Victor Frankenstein as played by Cushing should have been about in his mid to late 20s at most.
Deleted Role: Patrick Troughton appeared in a brief role as a mortuary attendant. Although his name is credited on some early publicity material, his scenes were cut from the finished film.
Those Two Actors: This is the movie that introduced Peter Cushing and Christopher Lee to each other. The pair became lifelong friends and starred in 22 movies together. This started when Lee complained that he didn't have any lines in the film, and Cushing said "You're lucky! I've read the script."