2. I have replaced the cpp_int with uint256_t for tests and I have created the seed from the large entropy from the pastebin link (maybe it workd also with cpp_int good but I don't know). The first seed word from libbitcoin VS is different than the first word from electrum (linux). The same problem as our libbitcoin test on windows/linux. I am debbuging now to find out the difference.
