As for the difficulty,
do I gain more depending on the difficulty?
Example:
web-ko1.gonspool.com:3333 (korea) diff 10000
web-ko1.gonspool.com:33331 (korea) diff 1000
web-ko1.gonspool.com:33332 (korea) diff 5000
web-ko1.gonspool.com:33333 (korea) diff 25000
web-ko1.gonspool.com:33334 (korea) diff 50000
diff 50000 gives you more coins?
Adoniso, yes it gives more coins but less frequently, you will earn the same on each difficulty, but it influences only frequency of the payout.