Scenario:
1. Game works fine
2. Go to verbose mode (type "verbose")
3. Game is broken, e.g when you try do drop or take something it only says "There's nothing here you can take"

Going back to e.g. "brief" mode doesn't fix it, save and reload doesn't fix it.

Only fix seems to be starting from scratch

So have you considered instead of native, you go ahead and use one of the many ways to interact with Zork?

I've never seen that happen, and I can't think of any time when I didn't use verbose mode for playing the Infocom games. Can you reproduce it at the very start of the game, or does it only happen under some more specific set of circumstances?

I suppose you could use the "$verify" command to see if the game file has been corrupted somehow, but I've never heard of that actually happening either...

Ok, I see now that the verbose was a red herring, I apologise. I tried it again and this time I can reproduce fully and reliably.

This is the scenario:

Pre-Condition:
1. Zork 1 must be version 88
2. Must use SCUMMVM (direct to zork1.dat file in the DATA folder)

Scenario:
1. Start game
2. type open mailbox (result: "Opening the small mailbox reveals a leaflet.")
3. save game
4. restore game
5. type take leaflet (result: "There's nothing here you can take" -- this will be the response to all actions such as open/take/drop you do from now on)

For info: $verify gives me this:
Verifying disk...
The disk is correct.

I think we can consider this thread closed seeing as:

1. this seems to be a specific SCUMMVM for Version 88 issue only, it is not inherent to Zork1 (issue doesn't arise via e.g. DOSBOX)

2. This issue does not exist with the zork1 Solid Gold version when using SCUMMVM -- it works beautifully with it

Ah. I haven't tried using ScummVM for Infocom games I'm old-fashioned enough to prefer plain Frotz in a terminal window. (Hey, it's still a step up from using DOSBox! :-)

I can reproduce your problem with ScummVM 2.2.0, but not with the current development version. One of the news items for the "Glk" (interactive fiction) engine was "Fixed savegame issues with several subengines". Specifically, there's a commit that says "GLK: ZCODE: Fix loading stack from savegames" that looks suggestive, but doesn't provide any further details.

If that's the bug you encountered, I guess it doesn't matter which version of Zork I you're using. Bad things may still happen when loading a savegame. Just different ones.