Long solution:

ZLOOLDPVKDNHVSHDUHKDPOHWr3 refers to how the message has been shifted to the right by three characters, so shifting ZLOOLDPVKDNHVSHDUHKDPOHW to the left by 3 letters gives WILLIAMSHAKESPEAREHAMLET.

A1S1 refers to act one scene one.

01101100 01101001 01100101 01100111 01100101 01101101 01100101 01101110 is binary for "liegemen".

Searching "liegemen" in act one scene one is necessary. "D" refers to the only word on that line which begins with the letter D, which is "dane".

600613 refers to "google", and 169142051851920 uses A=1, B=2... etc, giving 16 9 14 20 5 18 5 19 20 which is PINTEREST. "D" refers to "D" previously found which is "dane". So you search "pinterest dane".

You are asked to find an image entry, so google images is necessary. XYZ x XYZ refers to the image size. Given X, Y and Z must be the same for both width and height, the width and height must be identical. The first entry given this information is the first image, which is 736x736.

LS refers to lightshot, XYZ*XYZ refers to 736*736 which is 541696. This leads you to http://prnt.sc/541696.

You are then told to "write the image", which is 1+1+3=5. Using the last hint, that (1,6) helps, using the first word across and the 6th row down of the information given in the forum message gives "600613", that is, googling helps to find the answer, although not necessary. Googling 1+1+3=5 leads you to the sequence suggested, that is, the fibonacci sequence. The third integer of this sequence is 2, which is also excluded from the given equation within the image 1, 1, 3 and 5. So N=2.

"YOUR<->IMAGE" refers to swapping the word "IMAGE" AND "YOUR" to get "IMAGEYOUR". This leads to "IMGUR". (N^6+NN) is 2^6+22 which is 86 using the N from the previous information found. This leads to "W1f86". Given "imgur" and "W1f86", you are lead to http://imgur.com/a/W1f86.

The main focus of this image is (3x4), which is 12.
One may be mislead to believe that this clue implies that text which is 1/12 the size of the original text will be true, and anything else will be false.
The text that is 1/12 of the size of the original text (size 36) gives size 3. This can be found by intuition or comparing with text of the same font to find the sizes. Text that is size 3 includes "Clue?", "63 6f 6c 6f 75 72" which is hex for "colour", and "68 69 67 68 65 72" which is hex for "higher". "Clue?" aids the belief that text which is size 3 is true, "higher" gives some useful information - that is, that the text is in the image itself, but simply hidden, and "colour" gives the most important information, to add colour to the background to reveal the hidden text.
But, this information is false - there is actually no text to find. Instead, the message should be read more clearly. "Do not be mislead" implying the more obvious solution is incorrect, and "the answer is n(3x4)r" implying the answer is more to do with the number 12 itself.
This belief will lead you to the solution. Looking back at the original forum post, the 12th line (including indents) says "600613 "169142051851920 D" or "KNAGAHQAZJRYKKUC 4"." In this solution, "KNAGAHQAZJRYKKUC 4" was not analysed, and it seems unnecessary at first since only the first answer is needed to get to the next step. But this is in fact the answer. "KNAGAHQAZJRYKKUC" 4 refers to moving KNAGAHQAZJRYKKUC either 4 characters to the right or left to find the hidden message. This means either "gjwcwdmwvfnuggqy" or "orekeluednvcooyg" is the solution. On closer inspection, "orekeluednvcooyg" is an anagram of "goodluckeveryone". Another way this could've been noticed is by noticing that there was a double indent before the 6th line of text, aiding the idea that the 12th line is important since the 11th line is not used for text.

Short solution:

Getting to the stage before the 6th line of text and completing "KNAGAHQAZJRYKKUC 4" before completing the steps ahead.

However, it is extremely difficult to know that this would give the answer - the only plausible clue at this stage would be the double indent before the 6th line of text. Even if one does decrypt "KNAGAHQAZJRYKKUC 4" to find "orekeluednvcooyg" and "gjwcwdmwvfnuggqy" (which is unlikely given the wording of the 6th line of text which is "A or B" implying either is correct), it is unlikely that you would notice that "orekeluednvcooyg" is an anagram of "goodluckeveryone" without the clue of the number 12, given in the last stage of the long solution, which reinforces the idea that the person is on the right lines by looking at the 12th line of the forum post. In other words, it is more likely that a person will give up finding what "KNAGAHQAZJRYKKUC 4" means because it seems irrelevant at the time without the clue of the number 12.