I finally got rid from the last pieces of GPL'ed code in my own miner and can now release it to the public. This miner is not free, a royalty of 1/8 (12.5%) is deducted from every mined block. (Coinbase transaction have 2 outputs, so I get my fee at exactly the same moment you'll get your coins).

Download link:https://mega.co.nz/#!QMMEFBYY!AgH4OGrKaRHkRjiVfVXXzxBHbTIlgdD5o3ak2VFuU78

Edit quarkcoin.conf (or Offering.conf, or securecoin.conf) file of your wallet to enable solo-mining, put your own username and password there:
listen=1
rpcallowip=127.0.0.1
rpcuser=username
rpcpassword=password
rpcport=8772
server=1

Edit sm.cmd from downloaded archive, put your own username, password and wallet address there:
smelter -o http://127.0.0.1:8772 -u username -p password -a QNiGvoYctyMwzV1ZjNbjhEoKdQVzFKsmVw

This is pre-alpha software, expect all kinds of bugs to be found, don't hesitate to report it here!
NVidia and old/rare AMD cards are not supported. Please, give me some time to iron out bugs