I have only made small bits of progress, finding new uses for items.
Jim at the Sandwich Tribunal found instructions and recreated all the British Rail sandwiches. The sandwich depicted is marmite. A test eater (one of his children) described the taste as “fermented bouillon cube”.
Object #1: The British Rail Sandwich
I know, I thought I was done with this one too. Just as a reminder, the sandwich gave me strength, but also nausea and death, until I did:
>OPEN SANDWICH
You tear the transparent wrapper off the sandwich.
It turns out that the sandwich hasn’t yielded all its secrets, yet:
>OPEN SANDWICH
You find a note, reading: I am a captive food taster for B.R. Help me by saying the password near the restaurant and I will help you.
There’s a place where a “password” might work:
You are in a room with an obvious exit east and a sign dangling from the roof reading ‘K.TC..N’ and pointing north.
I haven’t had any luck with any words I’ve tested so far, though.
Object #2: The Mirror
Holding the mirror too long is dangerous:
You see yourself in the mirror and, not looking, fall down a hole.
You’ve passed away.
I had come up with a convoluted way of transporting the mirror via rucksack. The issue had a simpler fix:
>TURN MIRROR
OK
Now the item description (when seen in a room) is
A small face down mirror lies here.
and the mirror is perfectly harmless.
Object #3: The Harp
There is a harp made from rare woods here!
A perfectly natural attempt at PLAY HARP led to
You make an awful jangle.
Which in many games is just a signal that “your character can’t play this musical instrument, cut it out”. But no:
>TUNE HARP
OK>PLAY HARP
You strum – what else – ‘The minstrel boy’.
If I play the harp now for the dragon, the dragon is “pleased”, but still eats me if I try to walk by. I’ll have to experiment some more.
Renga in Blue 
Can you pick up the jangle?
Alas no. The game hasn’t gone evil enough to make you pick up indefinite sounds. It still might be coming.
Clingfilm! Clingfilm! Those damn sandwiches are all covered in cling film and it’s not just because it’s an American reconstruction, the Douglas Adams site indicates that it was always so. So the question is, how on earth did BR manage to make clingfilm crunchy?
Also I think it’s unfair to blame BR for the taste of the marmite sandwich. It wears its awfulness on its face, like the Crunchy Frog chocolate.
Ah there we go! I suppose the clingfilm ones weren’t takeaway sandwiches.
The mirror and harp puzzles are clever. If what I’ve heard about harps is true, the effect should last about half a turn. (Have you tried tuning the harp more than once?)
Yep, retuning the harp doesn’t seem to do anything.
“Fermented bouillon cube” is not just what Marmite tastes like; its what it is.
I saw the title and was secretly hoping you’d made a breakthrough with the pack of cards, which is maddening me.
What passwords have you tried? (I haven’t figured that puzzle out yet either.)
This is dumb, but have you tried “PASSWORD”?
Speak “friend” and enter? I like it.
Yep, it’s PASSWORD. (I had gotten a wee bit farther since this post.)
Gah, I was having a parser issue. “SAY PASSWORD” does nothing. Just typing “PASSWORD” is the answer.
I solved a puzzle in Quondam! Go me!
I happened to have the cross with me when I first visited the hermitage, so had never seen the result of doing that “wrong.” Just tested it out.
—
:N
You’re in a cell.
:S
As you leave, a passing hermit sees your possessions and slams the door.
You are in a hermetically sealed cell!
—
…Beware of puns!
Triple pun of death! (hermitage, hermit, hermetically sealed)
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