There was no episode of the show with a gumball machine as a major element.

A gumball machine that dispenses a different kind of pinball was a game idea Pat Lawlor had wanted to do for years. He was able to bring it to life in TZ seeing it as a very “Twilight Zone pinball thing.”

He also had wanted to put a physical clock on Funhouse, but a satisfactory design could not be realized in time, so the Funhouse clock became playfield inserts ... and the physical clock finally came to be on TZ.

Episode-wise, they are all excellent, but I’ve always been especially fond of:

To Serve Man - Richard “Jaws” Kiel as a Kanamit, aliens who come to Earth with solutions to all man’s problems. One of my first unforgettable lessons in being skeptical of things that seem too good to be true.

The Howling Man - A man seeking help is reluctantly allowed to enter a monastery (normally closed to the outside world) by a rather wild/sleep-deprived looking monk with a foreboding presence. Inside, he discovers a prisoner who incessantly howls from his captivity in a locked cell. The prisoner pleads with the man to unlock the cell and free him from the torture he’s enduring. But the “lock” doesn’t look like it’s strong enough to stop a toddler. There’s a transformation in the episode that is a rather impressive special effect for its time.