Looks like to mine Monero on NiceHash you need an appart software provided by them:
Source:
https://github.com/nicehash/Specifications/blob/master/NiceHash_CryptoNight_modification_v1.0.txtI dont know what a hell that mean: "....II. Concept
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Because there is no no extranonce1 and extranonce2, for NiceHash to
properly work with CryptoNight, we need to cut off 1 byte of nonce for
NiceHash, the rest - 3 bytes are for miners.
Iterating through 3 bytes gives 256 * 256 * 256 ~ 16M possibilities. If a
coin has 120 seconds block time, that gives us 16M / 120 = 140k/s, which
means that a single miner can be as fast as 140 kH/s before things go
wrong (miner starts making duplicate work). Since CryptoNight algorithm is
very slow and best miners reach around 1 kH/s at max, it is safe to cut
off 1 byte of iteration for NiceHash.
Unfortunately, currently available mining software is not adjusted for
this modification. It is a simple modification, but has to be performed,
else miners would get shares above target. "