Here is a transcription of the puzzle from the first room:
Top left tile:
Top right tile:
Bottom left tile:
Bottom right tile:
Since this has been around for so long, I figured I'd share my progress so far.
[NB: I did need to bruteforce the first cipher, and I would've never gotten it without doing that. I also bruteforced the other one, but don't plan to use the information until I figure out how I was supposed to have gotten the key.]
Some completely wild ...
Well I waited for really a long time but there's no response. So I decided to give the answer:
First look at paper #3, ´Ã£óEÕ´CDCE×Ç´BöB÷ÖBs"ÖBsróDBò÷Âä2æ2w§£2òô2ò÷Ä"Ä"Âóä"ÅBô"Ã2ó$Âòô"Âò÷ÂäÂæ£'ÄtróärôtwÆC"Ö2÷¢÷§Å:
Then paper #4, (21,22)(37,16)(15,19)(35,13) For #1.
Then paper #1:
Finally, paper #4:
You have lost a:
First note that each clue:
Now we can also see that:
Now use the diagrams. What we have here are:
These can be constructed like so:
So now putting the words in green together, we know you have lost:
The first thing to do is work out what shape each diagram represents. Across each row, these are in turn:
What do we now have? The highlighted cells on these 8x8 grids of squares:
Now, we have identified 16 letters of interest - the same number as the number of "+/-" commands in Step 2 of the puzzle instructions. What we must do next, ...
The answer is:
Look down on the top layer. One long word is very prominently visible. That word is:
When we do that, we can spot another word in the new grid:
Doing that, another new word becomes apparent:
Excavate this area down to level 4, and we get the following new grid, concealing the words:
Excavate this down to level 5 to find:
Excavating this ...