[Mourningfall]

llyair you're so clever o:

I'm definitely not intelligent enough to actually answer these questions,
I feel like a goldfish compared to you eggheads. But I love to challenge myself and these puzzles are definitely stimulating

The spoiler is not an answer to No.4, just my silly idea on how someone might go about finding it

My guess is the entire file is a Markov chain.

Using python's counter object someone who actually knows what they're doing could make some kind of text probability calculation.
It's probably be something simple like:

from collections import Counter

text = open("markovhaystack.txt").read().lower()
letter_freqs = Counter(text)

word_freqs = Counter(text.split())

Of course I have no idea what I'm saying, but any data collected successfully from the frequency in which these words are appearing could be useful in determining the probability distribution. *shrug*
Which I'm blindly assuming is important for no reason at all. ^^

Just an idea. Enjoy yourselves