aaru: There are many bugs with the achievements, as I have mentioned in several posts back in May. I have given up and hope it will be fixed for BK Version 3.
(hide) If you want to play a game with an opponent of a similar level, you can define a required BKR range for a new game invitation. Then nobody with a BKR outside this range will be able to see/accept it. (Katechka) (show all tips)