After fixing a dumb bitwise math bug and fixing a piece of the insert object logic (after removing an object, it wasn’t setting siblings correctly), things are looking pretty awesome. I would call the following a pretty successful test!

ZORK I: The Great Underground Empire
Copyright (c) 1981, 1982, 1983 Infocom, Inc. All rights reserved.
ZORK is a registered trademark of Infocom, Inc.
Revision 88 / Serial number 840726

West of House
You are standing in an open field west of a white house, with a boarded front door.
There is a small mailbox here.

>n
North of House
You are facing the north side of a white house. There is no door here, and all the windows are boarded up. To the north a narrow path winds through the trees.

>e
Behind House
You are behind the white house. A path leads into the forest to the east. In one corner of the house there is a small window which is slightly ajar.

>open window
With great effort, you open the window far enough to allow entry.

>go in
Kitchen
You are in the kitchen of the white house. A table seems to have been used recently for the preparation of food. A passage leads to the west and a dark staircase can be seen leading upward. A dark chimney leads down and to the east is a small window which is open.
On the table is an elongated brown sack, smelling of hot peppers.
A bottle is sitting on the table.
The glass bottle contains:
A quantity of water

>take bottle
Taken.

>w
Living Room
You are in the living room. There is a doorway to the east, a wooden door with strange gothic lettering to the west, which appears to be nailed shut, a trophy case, and a large oriental rug in the center of the room.
Above the trophy case hangs an elvish sword of great antiquity.
A battery-powered brass lantern is on the trophy case.

>take lantern
Taken.

>move rug
With a great effort, the rug is moved to one side of the room, revealing the dusty cover of a closed trap door.

>open door
Which door do you mean, the wooden door or the trap door?

>trap
The door reluctantly opens to reveal a rickety staircase descending into darkness.

>i
You are carrying:
A brass lantern
A glass bottle
The glass bottle contains:
A quantity of water

>take sword
Taken.

>d
You have moved into a dark place.
The trap door crashes shut, and you hear someone barring it.

It is pitch black. You are likely to be eaten by a grue.
Your sword is glowing with a faint blue glow.

>turn on lantern
The brass lantern is now on.

Cellar
You are in a dark and damp cellar with a narrow passageway leading north, and a crawlway to the south. On the west is the bottom of a steep metal ramp which is unclimbable.

>n
The Troll Room
This is a small room with passages to the east and south and a forbidding hole leading west. Bloodstains and deep scratches (perhaps made by an axe) mar the walls.
A nasty-looking troll, brandishing a bloody axe, blocks all passages out of the room.
Your sword has begun to glow very brightly.
The troll swings; the blade turns on your armor but crashes broadside into your head.

>kill troll with sword
You are still recovering from that last blow, so your attack is ineffective.
The troll swings his axe, but it misses.

>g
You charge, but the troll jumps nimbly aside.
The axe sweeps past as you jump aside.

>g
The troll is staggered, and drops to his knees.
The troll slowly regains his feet.

>g
The fatal blow strikes the troll square in the heart: He dies.
Almost as soon as the troll breathes his last breath, a cloud of sinister black fog envelops him, and when the fog lifts, the carcass has disappeared.
Your sword is no longer glowing.

>score
Your score is 35 (total of 350 points), in 18 moves.
This gives you the rank of Amateur Adventurer.