i_a luigi1111 : I'm not entirely sure from your pastebin, but you need to do an "unpack" after the hash, not a "pack" or "compress". you shouldn't be touching the y-coord at all like that

github.com/monero-project/monero/bl…b/master/src/crypto/crypto.cpp#L481 `hash_to_ec` does a `...frombytes..` call found here -> github.com/monero-project/monero/bl…aster/src/crypto/crypto-ops.c#L1284

that last bit is not part of the y-coord, and is used to determine the x-coord sign