Well, i am going to organize a tournament for my club coleagues (invite only, =<10, 1 round robin, no groups, 3 days per move) and i really really need to limit the number of games played at once. Time is not an issue, but i don't see any possibility how to prevent the system start all games at once.

I would like to configure:

In 10 people - 9 games each player (45 games total), 3 at once (15 total), when 8 from these 15 games are completed, start next wave with 3 games each (next 15).

Thanks for your suggestions in advance.

There is an option in the advanced tournament settings called "Concurrent games per opponent". This can be set to either 1 or 2.  When it is set to 2, then all games for the tournament will start at once, so, if there are 8 people per group, each player will start 14 games at once. When it is set to 1, then that number is halfed, and once one game is completed, the second game between both players will start right away.

There is no way at this point to have the games come as you have suggested. I would recommend making a tournament with small groups, and setting the concurrent games option to 1.