So when I sell 4 UBQ from bittrex UBQ address there is not transaction fee either for me or the buyer?
Yes this is
not a transaction fee that is only
commission fee.
When you transferring funds from the other source theirs
will be a transaction fee , for example you have UBQ in bittrex and you want to transfer your UBQ into your UBQ personal wallet theirs will be a transaction fee for this that will deduct to your UBQ current balance.
There is only the commission from the bittrex site?
Yes if you trading only but if you want to transfer your funds to your personal wallet theirs wil be a transaction fee.
So how do bitcoin appear in my BTC address?
Just withdraw it.
The miners are not payed for this exchange?
Nope , miners payed by reward if they mined a block their will be a reward.They including only the transaction after they got a block the transaction that they include it will got a confirmation.