Puzzle out the Cryptogram Patterns

Question

So I haven't posted very many questions and I'm not yet very good at figuring out how many clues to include. In addition, I realize that the key behind the third cryptogram is not at all obvious so it might need some more help but I don't want to give the game away. I'll give it until Monday and then I'll post some more obvious hints.

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Can you decode each of the cryptograms below and then answer the challenge they pose?

ISAEBZMEIYIQWXXOIYSCIZSJCOTFSYJALIAJQEICJGVMEIQOSJGMIPMJYGBMMEIAESOOIGVISYFSYJAMBBOYASGLBMESMRBFDICTKWJAUOTMEIQOSJGMIPMJYHICIOTMEIIPQOSGSMJBGBZMEIMCWIQWXXOI

XKEJGBVUUCMZCFSAKNFZEJCKEAABCRVAACJMICBFMYCVGBGFRBCJAJXAKCOVQFMCCVGBIXFASCUNVSABCEMYCJUXFMZRVAACJMSVJCEMFDECABCXVJCSFQRUCFYCVSIEAQVXICAJFGHXAKFYCMAFNXICGVESCABCXJCDEFJCVMCRFRBVMX

CIZQYNDRFRYAKPQLRNDRRQQKDZDPYEPQLRJDGHSZQOVYBERQAQLAGYFCQLFVYFRKDDENQCLNHLPMHFMCRQYRRMDJDFRHLFTDOTCGGMHWDHGGRMODDEGHCLRDXRFRMDYLPDOGZCLNEHRRDOLIQODHAMHLPRMDOYGDRMHRRMDICOFRHLPRMCOPFMHODRQDLFYODHYLCUYDFYJFRCRYRCQLNQQPGYAKEYSSGCLN

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There may be solutions to the puzzle-within-the-puzzle that I haven't thought of yet. Any such solutions will receive an upvote but will not be accepted as the answer unless the answer I was thinking of is never found (doubtful) in which case the most upvoted answer will be accepted.

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Clarification on the hidden challenge:

NAFJREVATGURUVQQRAPUNYYRATRJVGUFBZRGUVATYVXRNRAPELCGFGBAJVYYORPBAFVQRERQVAFHSSVPVRAGLBHZHFGRKCYNVAGURCNGGREAGUNGYRQGBNRAPELCGVATNFA

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End of the first day hint:

As @JasonPatterson hinted at on the answer by @GentlePurpleRain there are clues in the third cryptogram. In fact, the first three sentences of the cryptogram each contain a clue. Three sentences, three clues, three cryptograms. That nae be a coincidence, laddy.

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End of the second day hint:

For the first cryptogram: Don't think of the key as starting with "A encodes to S". It starts with "Q encodes to K". Now, why does it start with "Q" and why does that become "K"?

For the second cryptogram: The words from the first clue with the Z and J are there for a reason. Those are rare letters. Where have you seen those words together before? (@GentlePurpleRain has already solved this one)

For the third cryptogram: @JasonPatterson already found the key word in the encoded clue. The method of applying it may be fremd for individuals vacant of experience. How can you go from the resulting mess back to a letter?

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End of the third day hint: (not optimized because kids just started screaming)

1) Your clues are: "IF YOU GET STUCK DONT GET TOO KEYED UP". It starts with "Q encodes to K". Try looking down. Recall that Q is the 17th letter of the alphabet. But what if two letters encode to the same result? That's not allowed.
2) (solved)
3) Your clues are: "JUST KEEP GOING AND HASH IT OUT". The method of applying it may be fremd for individuals vacant of experience. After you hash it out, you have to convert it back to a number. Try to use as little of the mess as possible to get a unique encoding. But what if two letters encode to the same result? That's not allowed.

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Beginning of the second week hint:

1) If you're viewing this on the desktop site - I.E. not the mobile site - and you look down, what do you see with keys on it? Since Q is the 17th letter of the alphabet, what comes 17 keys after Q? What comes 23 keys after W?
2) (Solved)
3) After you hash it out, you need to get back to a letter. How can you take the first tiny bit of the hex mess and modify it to get a decimal equivalent to a letter? How little a bit must you take to get a unique result?

Answer 1

Cryptogram 1 - Based on the hints, here is the encryption method:

On a QWERTY keyboard, the keys are numbered from L->R and T->B, as shown below. The plaintext key number plus its alphabet number determine its associated ciphertext letter. For Q, 1+17=18, so the CT letter is K.

If the CT letter has already been used, then the next available key becomes the CT letter. For T, 5+20=25, but N has been used so the next available letter is M.

The encoding table is shown below.

Cryptogram 3 - Here is the encryption method:

Step 1 - make MD5 hash for each letter of the alphabet, individually
Step 2 - start by taking the first digit from each hash, then convert to decimal
Step 3 - use mod-26, add 1 and select the equivalent letter of the alphabet
Example for plaintext D - the first digit of the hash is f which is decimal 15. Add 1, then select P for the ciphertext.

Step 4 - if the CT letter has already been taken, then repeat steps 2 and 3 with the first 2 digits of the hash. Keep adding a digit from the hash until a unique letter can be selected for the CT.
Example for PT L - a unique letter is not selected until d20 (3 digits) is used. Convert to 3360 (decimal) then mod-26 plus 1 is 7, so the CT character is G.

The encoding table is shown below.

Answer 2

-- Partial solution --

The cryptograms prove relatively easy to decrypt. Their solutions are as follows:

Cryptogram 1

EACH OF THESE PUZZLES ARE FAIRLY BASIC DECIPHERING THE PLAINTEXT IS NOT THE CHALLENGE AS BASIC TOOLS CAN DO THAT JOB VERY QUICKLY THE PLAINTEXT IS MERELY THE EXPLANATION OF THE TRUE PUZZLE
Key: ABCDEFGHIJKLMNOPQRSTUVWXYZ CORVHBNMEIQDTWLXPJAYKGUZSF

Cryptogram 2

YOUR CHALLENGE IS TO FIGURE OUT THE PATTERN BEHIND EACH CIPHER TRY TO EXAMINE EACH BY ITSELF AS THE UNDERLYING PATTERNS ARE UNIQUE THEY ARE SIMPLE IDEAS BUT MAYBE TRICKY TO IDENTIFY BECAUSE THEY REQUIRE AN EPIPHANY
Key: ABCDEFGHIJKLMNOPQRSTUVWXYZ THEQUICKBROWNFXJMPSVLAZYDG

Cryptogram 3

IF YOU GET STUCK DONT GET TOO KEYED UP DONT BE LAZY OR JUMP TO CONCLUSIONS JUST KEEP GOING AND HASH IT OUT THE BEST ANSWER WILL HAVE ALL THREE PLAINTEXTS THE UNDERLYING PATTERN FOR EACH AND THE RULE THAT THE FIRST AND THIRD SHARE TO ENSURE A UNIQUE SUBSTITUTION GOOD LUCK PUZZLING
Key: ABCDEFGHIJKLMNOPQRSTUVWXYZ CMIEPSLAFBKNHGRDOTZWQJVXUY

Right away, the key for the second cryptogram jumps out. It is

obviously the common pangram "The quick brown fox jumps over the lazy dog" with duplicate letters removed.

The keys for the first and third cryptograms continue to elude me, though. I suspect that is the part of the puzzle that is intended to be difficult.

It doesn't seem like they can be following a similar pattern to the second cryptogram, because

any phrase with repeated letters removed would likely still look like English for the first few characters (until there is a repeated letter), and would probably have most of the more common letters (ETAOIN SHRDLU) near the beginning of the key.