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. "
This happens only if you use third part miners on their pool. Their software on their pool can be use out of the box.
This is the main reason why people use nicehash..