The Cryptic Safe

Question

EDIT 9/20/22:
I have found a mistake in the puzzle, and have provided a hint to help get through it. The hint is not there strictly because of the mistake, and was intended to be added anyway (adding it is what caused me to come across it). This mistake does not strongly hinder your ability to solve the puzzle, as there are still many steps that can be completed without this affected portion.

EDIT 7/19/22:
If you are solving this and are stuck , please let me know where you are stuck so that I can help! I would like to add more hints, but am unsure as to what I should be hinting towards.

---

A safe was dropped off at a local police station, supposedly belonging to a highly wanted criminal. Police have suspicions that whatever is inside the safe will lead to this person’s whereabouts. Only if they’re able to understand those contents, that is.

The front of the safe is just like any other, except instead of your typical dial, this safe has a keypad of colors.

There was a note securely taped to the front. It seemed as if this criminal was prepared for somebody to find it.

“Everything has a reason”

In addition to this note, it seemed as if somebody had drawn all over the front of the safe. A seemingly random pattern of red and purple dots lined the safe above and below its door.

After some time, one person at the police station had noticed something interesting about the colorful keypad, and not long after (and with a fair bit of confidence) was able to open the safe. Once the safe had been opened, though, everything made even less sense.

Inside the safe was nothing more than two pieces of paper, as well as some random numbers, letters, and drawings scratched into the walls and door of the safe.

The contents of the safe are shown below (colorblind friendly versions are available below).

The Safe

The Letter

The Photo

---

Colorblind Friendly Info

Text version of the colors on the top and bottom of the front of the safe. r is red and p is purple.
Top: rpppprrprrprpppprrprrprrprprrrpprrpprprpp
Bottom: rrpprpprrppprpprppprpprrpprrrprrrrrpprprrprrprrp

Color-free version of the keypad.

---

Hints

Hints will be added when I feel they may be needed. Them being added is not dependent on time or progress made

Hint 1 (Added 6/24/22):

One serving contains about 450mg

Hint 2 (Added 6/27/22):

Unless obviously a letter, it's probably a number

Hint 3 (Added 6/27/22):

Not all o os mean the same

Hint 4 (Added 7/11/22):

Photo is to upper equation as dots are to lower.

Hint 5 (Added 7/11/22):

A key will be needed

Hint 7 (Added 7/11/22):
Please note that this hint contains confirmation of something mentioned within @FrodCube's answer or its comments

".00"+"8917"=_____

Hint 8 (Added 9/30/22): Please note that this hint will contain more information than normal, and will be less (if at all) cryptic, given the time that this puzzle has sat

There are four main pieces to this puzzle, as hinted at in Hint 4. Steps 1 involves using The Photo and then step 2 uses the top equation. Step 3 involves using the grid in the wall, the letter, and the dots on the outside of the safe, and then step 4 uses the lower equation.

Hint 9 (Added 9/30/22): Please note that this hint will reveal one small part towards the solution, though some of this is due to my error. If you do not wish for a spoiler like this, please allow me about a day to update the puzzle. Also note that although there is an error, progress can still be made on this puzzle, and it only affects one section (out of four).

The dots on the outside of the case have these meanings: TOP: tacsgggkzzki (this is where the error is, and this would not be found with the given photo of the safe). BOTTOM: grpflltxttwofggg

---

Anything below this point is not part of the puzzle, and should not be referenced to find clues.

So now it is time for me to ask you:

How did the cop open the safe? and
Where is the criminal hiding?

This is my first time writing a puzzle of this length and complexity. It is very possible that there are some flaws, and even mistakes (though I have gone over it several times). Please let me know if you find any!

Note: The letters on the flag in The Photo only relate to the colors they're on top of.

I will answer any question in the comments, given that it does not ask about the puzzle itself or how to solve it (i.e. I would answer "Is there a significance in the way the post is worded?", but I would not answer "Should I be focusing on the photo or letter first?").

Please be thorough in your answer. I am looking for the steps you took to get to each piece of information, and how you used it. I am happy with and encourage partial answers as well, I love to see the different levels of progress!

Good luck!

Answer 1

I'll start with a partial answer, since I'm stuck. Here's what I have so far

EDIT 1: added a bit more progress

The safe:

The police office probably noticed that only six out of nine buttons were dirty, i.e. used. Since those buttons correspond to the colors of the rainbow, he probably pressed them in the order R O Y G B P.

The letter:

The message decodes by using the substitution written in the back of the safe: for example "o5" means that the "o" in the message should be substituted with the 5th vowel counted as "aeiouy". By doing this we find

I'm sure you can read this,
though something is off.
This is the first step to the
long, long journey you are a
bout to partake. Read
everything carefully, as you
don't want to make a
mistake. Hidden in this safe
is where I am hidding, and
though I doubt you will find
me, I know you'll keep
trying. Make sure not to lose
this note; you will need
everything I have wrote

Also important to notice that five letters in the message are written in a different font. In order they read "I M G U R".

Finally there are two mistakes: "hidding" is spelled with an additional "d" and the final word "wrote" should probably be "written"

The picture

There are five images paired with arrows. The arrow probably symbolizes whether the letter encoded by the picture is upper or lower case. The way I have interpreted them, but I don't think it is fully right, is:

"x k X N L", since "x" marks the spot in the map, "k" is the symbol for potassium, abundantly found in bananas, "N" in the semaphore flag alphabet, and "L" because of the shape drawn.

Interpreting this as a imgur URL gives the following picture. There are two pictures, one the negative of the other, with written "F * I" and a red circle telling us to take the second option. This might mean to take the "negative" of some result, but I don't know which.

What's left:

The picture on the door should mean "Upper Case", since it points to the "upper" of the two "cases", but I don't know where it should be used

The shape in the top right inside the safe is the same shape as the lines in the picture message, but I don't know what it means that it is followed by "o o"

I don't know how to decode the upper and lower "equations" inside the safe and similarly the purple and red sequences outside the safe. The only bit of progress on the top equation comes from SQLnoob's comment where if you interpret the numbers as the hex codes for ASCII, you get that the numbers combine to 8917, but it is unclear how to combine this with the ".oo" at the beginning. All the ?8917 imgur pictures (with any character for ?) are either non-existent or unrelated to the puzzle.

I don't know the meaning of the two grids with the bottom right corner shaded inside the safe

That's what I have. It's not much but I hope it can start a discussion.