Pokemon Cafe ReMix (Mobile)

[Gummy Frog]

Hi! I've been curious about extracting files from Cafe ReMix for a while. I'm using the mobile version since it's easy to run on an emulator.
I managed to extract what was in the root/data/app section since I'm pretty sure that's where the files are - I found sound data and some other things - but all the data is compressed in .arc formats.
I downloaded peazip which can read the .arc files, but they seem to be encrypted and need a key.. I'm not exactly sure how to decrypt these. Anyone have any idea where to start?

[Shade]

Utilize this script and QuickBMS to get at least part of the way. The files that come out are unsorted .dat files so it's not much better but it's at least a step closer.

Code:

# Pokémon Cafe Mix .ARC (script 0.1.1)

comtype deflate
get DUMMY long
get DUMMY long
get DUMMY long
get DUMMY long
get FILES long
get DUMMY long
get DUMMY long
get DUMMY long
for i = 0 < FILES
    get NAME_CRC long
    get TYPE long
    get BLOCK_SIZE long # just like ZSIZE aligned
    get OFFSET long
    get XZSIZE long     # aligned for encrypted
    get ZSIZE long
    get SIZE long
    get SOME_CRC1 long
    get ZERO long
    get FLAGS long
    get SOME_CRC2 long
    get ZERO long
    if FLAGS & 0x100
        log "ENCRYPTED/" OFFSET XZSIZE
    else
        if SOME_CRC2 == 0
            clog "" OFFSET ZSIZE SIZE
        else    # yeah FLAGS 1 and XZSIZE != ZSIZE, no way to guess
            log "ENCRYPTED/" OFFSET XZSIZE
        endif
    endif
next i