I sort of got stuck, but that's probably just me. I'll keep at it for now. In the meantime, some thoughts...
1) Your attempt to keep your responses "colourful" have rendered them a bit confusing. You've taken out the text that helped indicate what the problem is and just replaced it (as far as I can see) with a blanket "What now?", which doesn't indicate what has gone wrong. I am guessing that you wanted to give the impression that something has happened and now you're moving on, but in the case where the input is just plain wrong, it makes no sense. Here is a sequence, in a place where there is no lock.
> smash lock
What now? (lock)
> x lock
What now?
> take lock
What now?
> drop lock
What now?
> pick lock
I'm not sure what you mean.
The first one would originally have been something like "I can't see that (lock)". Now it says "What now? (lock)", which is less than useful. Also, the generic "What now?" response hides that something has gone wrong, which is valuable feedback for someone playing your game. It helps to differentiate that which works from that which doesn't.
2) Some things to be edited:
- "It's red paint is crumbling off in large patches -> "It's" should be "Its" (possessive has no apostrophe).
- "At the front of the shack is a window pain which has been left slightly ajar." -> "pain" should be "pane"
- "Anyway, It's an enjoyable walk but there's nothing much here apart from trees and mud. " -> lower-case "it's".
- "Its low, with only one storey plus a little attic ..." -> "Its" should be "It's"
3) I found your use of "Anyway" in a couple of places as a sort of transition from introspection to be a bit jarring. I would drop that. You don't need it.
4) Examples to illustrate the next point:
COTTAGE FRONT
I'm stood under the rustic...
GROUNDS
I'm stood in the green, dry, muddy...
A GARAGE FRONT
I'm stood in the middle of...
I trust you can see the repetitive nature of this. I would also lump in the others like "I'm sat...", "I'm walking...", etc. You do quite well in other areas where you just have the description without the need to lead off with some sort of "I" sentence. Your writing is strong enough that you can be descriptive without the having to resort to that formula.
5) I'm intrigued by the use of colour. Right now, everything with colour has been green except the red shack. If that's not actually significant, then you might want to mix things up a bit, as it looks like a pattern of some kind. (And if it is significant, then hooray for me. lol)
6) I'm really enjoying your writing. Only a few typos (some minor comma errors as well that I didn't mention - I can list those for you as well if you like), and your style is fluid and easy to read. Very enjoyable!
7) While incorporating time is seductive, you have to be very careful. For example, along the path, you mention "yet the yellow dusk light is still just about strong enough to illuminate the way before the darkness truly sets in." So it's nearly sunset. Then following the path further, you say, "After following the forest path for another twenty minutes or so, the suddenly familiar sight of the crusty old red gate at the head of my uncle's drive comes into view." So time has passed. Then if you go back to the path, it once more says that sunset is imminent - yet probably the better part of an hour has passed. It can be a slippery slope to try to track all of that. (Also, it begs the question of just how dark it is once you reach the cottage.)
That's all for now! I see you have updated since my last comment, so I thought I give you some more to ponder.