Let's say I am playing a computer game (overwatch, for example) and I've just met some friendly people. In overwatch, there are rounds. One round usually lasts no more than 20 minutes, but it is possible to play round for more than an hour. I want to ask them about their overall time spent in overwatch. Normally, I would use present perfect tense ( How long have you played this game?) but I'm not really sure. And, when I want to ask them about the amount of time they spent during this one round, I will use perfect continous (How long have you been playing this game?) Is it right?
If someone asked me, "how long have you played this game?", I would take it to be asking about the amount of time since I started playing - i.e. if I started playing a year ago, I would reply, "about a year".
I would say the same thing if someone asked me, "how long have you been playing this game?" The verb tenses "played" and "been playing" are different -- but "been playing" means that the playing is still going on, which is definitely the case if you're asking inside the game.
For example, I played Quake 3 for 2 years. Since I'm no longer playing Quake 3, "how long have you been playing" isn't appropriate - "played" is the better verb tense because the action concluded in the past.
None of this has any bearing on the current round. In my opinion, the better way to ask that question is to change the noun, not change the verb tense. For example:
How long has this round been going on?
^^ This means that the round is still ongoing.
How long was that round?
^^ This means the round has ended.