I never got around to doing the level since I got stuck at the start. I just got past the hi so here are my thoughts.

Room with green entrance: No idea


Mint entrance: These probably relate back to panels in previous levels. I only solved two panels in there. I think maybe the white side references level 1 and the black side references level 2.
My two answers spoiler: For the lavender one, the answer was "listen" and I guess it is the answer because there is a middle lavender and bottom black that both have the answer "listen" (one at the arcadian and the other in the lavender area by the big letter wall). The three whites are "remember" which are all right next to the entrance of level 2.
I could just find the rest of these answers and post them here if you want because they are tedious to find.


Orange entrance: Clearly the pictures resemble the library 2nd floor. Maybe the glass color on the roof relate to a cipher like typical orange blocks or maybe take some letters from each painting name? 12 pieces of glass, but only 11 letters?


Yellow entrance: The 8 numbers might result in 8 letters that get rearranged to solve the gray/cream block? The gray block with prompt "answers" reminds me of the level 2 green with the same prompt block in front of the magenta wall. Maybe after solving some panels the numbers will tick down.
Spoilers for early level 2: Then, we can take the first letters of each block like the level 2 letter wall area.
Also the ceiling looks like the dot puzzle from level 1 to get to the pilgrimage. I wonder if that is significant.


Pink entrance: Can't enter


Black Hi: I tried to wallsnipe "Hi", "H", and "I" which did not work. Also tried to use it as a teleport gate like the pumpkin patch which did not work.

I want to note that the skylight for the orange entrance does remind me of the ciphers. Also the mint area's black/white change makes me think the white side is level 1 and the black side is 2. (the middle one with the blue and yellow actually splits the 2 sides in half) For the green entrance, we might FINALLY have an answer to the random 3 by 3 by 3 blocks in level 1 as the lavender blocks remind me of it.
The Hi is probably for the door we cant access
Edit: the "ciphers" refers to the ones in the pumpkin patch which would make sense since the doorway is orange so lets tackle that first.