As you mentioned that you have done calculation, so based on 6000GH/s how much BTC will be paid to donator/miners monthly? (both depends on how many HAS they get right?)
It is hard to calculate the exact amount of Bitcoins distributed daily/montly since that will depend on the pools luck in finding blocks.
Payouts will be done daily not monthly.
You can use any Bitcoin profitability calculator to get a good estimate of the amount that in theory will be distributed each day.
Yes, the Bitcoins will be divided among all HAS, the more HAS you have in your HAS client the more Bitcoins you will be rewarded as Proof of Stake.
If your HAS is at an exchange then the exchange will get your daily Bitcoin payout.