I need some clarification about withdrawal process: I see you apply a dynamic w/d fee linked to current network fees which is also displayed in w/d interface, that's crystal clear.
But I also see a "unpaid deposit fee " showing me zero ( maybe because I did not make a deposit in a long time now) which I don't understand what it is connected to (perhaps to the network fees at the time the deposit is made) and therefore I can't imagine what order of magnitude it is: is it comparable to the classic w/d fee mentioned above or what?
No, the unpaid deposit fee is generally a lot smaller and depends on 1) how expensive Bitcoin transactions are at the time you withdraw or tip another player, and 2) how many deposits you've made since you last withdrew or tipped someone. For example, say you made 20 deposits and now want to withdraw your profits. You'd have to pay the normal withdrawal fee, and what it costs to consolidate all the deposits you made:
total fee = withdrawal fee + (20 * consolidation fee)
So, making a lot of deposits will only incur additional costs for you, not for other players (and that's one of the reasons we can offer really cheap withdrawals).
Also, if I make different withdrawals do they come from the same address or will a brand new address be used for every transaction?
We wouldn't be able to send from an address that hasn't received funds (i.e. doesn't have any outputs associated with it), but we don't consolidate deposits into a single address, if that's what you mean.