The razor glove worn by actors and crew members during interviews wasn't actually a screen used glove from any of the Nightmare on Elm Street films. The glove was actually made for the production of Never Sleep Again by independent special effects artist Jeffrey Daniel Flynn.
The DVD box set includes extended interviews and a preview of Heather Langenkamp's documentary, I Am Nancy (2011), on disc 2.
The documentary covers the entire history of all the Nightmare on Elm Street movies (and the short lived TV series) with the exception of the often panned reboot film, the only entry in which Robert Englund did not play the role of Freddy Krueger.
The title-card for Nightmare On Elm Street 4 shows up on-screen at the 1:44:44 mark exactly - that's 1 hour, 44 minutes, and 44 seconds into the movie.