Hi nicoboss, i am working to fully support nsz in NSP Indexer.
I have right now a full decompression routine that devliver the same result as nsz command line.
But i noted that the original NSP and the decompressed NSP have a diff.
both works but i think there is a mismatch in offsets into the decompressed one

Original NSP
pfs0:/0100ea80032ea0000000000000000004.cert 000000000000-000000000700

Compressed/Decompressed NSP
pfs0:/0100ea80032ea0000000000000000004.cert 000000007df0-0000000084f0

Edit:

I modified the way i recreate the main PFS0 and now i have perfect match from Original to Compressed/Decompressed
same sha256sum!
i just started to put files from fileBodyOffset instead of starting from fileBodyOffset+ dataoffset (that in nsz is shifted)