tense - What is the meaning of "I would not now have exchanged" in this sentence?

  That night, on going to bed, I forgot to prepare in imagination the Barmecide supper of hot roast potatoes, or white bread and new milk, with which I was wont to amuse my inward cravings: I feasted instead on the spectacle of ideal drawings, which I saw in the dark; all the work of my own hands: freely pencilled houses and trees, picturesque rocks and ruins, Cuyp-like groups of cattle, sweet paintings of butterflies hovering over unblown roses, of birds picking at ripe cherries, of wren's nests enclosing pearl-like eggs, wreathed about with young ivy sprays. I examined, too, in thought, the possibility of my ever being able to translate currently a certain little French story which Madame Pierrot had that day shown me; nor was that problem solved to my satisfaction ere I fell sweetly asleep. I examined, too, in thought, the possibility of my ever being able to translate currently a certain little French story which Madame Pierrot had that day shown me; nor was that problem solved to my satisfaction ere I fell sweetly asleep.
 Well has Solomon said -- “Better is a dinner of herbs where love is, than a stalled ox and hatred therewith.”
 I would not now have exchanged Lowood with all its privations for Gateshead and its daily luxuries.

-- Chapter 8, Jane Eyre

1. 
   

   Does the last sentence mean that the decision in the past has a relation with the present, that is, I haven’t changed my mind still now?

   
   


2. 
   

   Or is it just a recollection, in the present, that I came to that decision in the past?

   
   

If the first is right, the original sentence is different in the meaning from this sentence, isn’t it?

I decided then I would not exchange Lowood with all its privation for Gateshead and its luxuries.

If the second is right, there’s no difference between the original and the above sentence, isn’t it?

Answer

SHORT VERSION:
Although this looks like an ordinary present perfect, you are dealing with a modal verb here, and the sense is that you describe in your (2).

LONG VERSION:
Here's how it works.

An ordinary present-tense indicative sentence would read

I will not exchange Lowood … for Gateshead …

If tomorrow you look back and remember what you said today, you cast this into the past:

I would not exchange Lowood … for Gateshead …

But suppose what you say (today) is something like:

Even if you paid me a million dollars I would not exchange Lowood … for Gateshead …

When you come to cast this into the past, you have a problem: it’s already using the past form to express the ‘hypothetical’ character of your assertion.

In such cases, English uses the construction past-modal + have + past-participle to express the simple past sense of the past-modal.

It’s a present perfect construction only in form; the sense is simple past.

Accordingly it means exactly what you say: a recollection, in the present, of what you decided in the past.