At about 27:40, Giles mentions Bovril. I don't know whether this is substantial enough to mention. Bovril is the trade name for a salt, thick meat product made and sold in Britain. It can be spread on bread, but Giles speaks of a "cup of Bovril." Bovril can be diluted with water, or less commonly milk, and drunk as a beverage. Bovril is little known in the United States. The purpose of mentioning Bovril seems to be to stress Giles' Britishness.
The synposis says Buffy has a nightmare the evening before her first day at Sunnydale HS. I thought it was a prophetic dream, not a nightmare. We do see the Master, and also the crucifix that she later receives as a gift from Angel. Note, the script as I have it specifies certain images, such as a pool of blood, that do appear on screen, but it also calls for images and words that DO NOT show up:
"ANGLE: THE ALLEY
"And the man, face down, unable to crawl, clawing his way along the ground in terror – and his body is YANKED out of frame with incredible speed.
"ANGLE: A GIRL IN BED
Tossing and turning, as the camera moves down to reveal the shadow of someone – something – approaching her – and we hear an impossibly low voice:
I’ll take you… like a cancer…
I’ll get inside you and eat my way out…"
This page says zombies are mentioned in "Welcome to the Hellmouth." I guess that means in Giles' first conversation with Buffy. But zombies are also shown on screen, during Buffy's dream. Should that be mentioned?