to add fix difficulty add .diffnumber behind you wallet adrees in the miner confi file
So i would be : pool.solace-coin.com:4500 -u walletadress.600 -p
(30x20=600)
Thank you... that option give me a lot of room to tests but 600 is losing a lot of work (only 30% accepted).
I'm from Brasil... maybe the transmission takes too much to be sent? I will try others difficult options lower and higher (now testing 1000) to see if I can reach at least 90% non-rejected... I will try others pools too.