RKC in , starting in 4

Bidding diagrams
4     Asking for aces with
 4   1 or 4 aces
  4  To play if only 1 ace
  4  Asking for Q
   4NT Q, no extra
    5To play
    6To play
   5 Q, extra CUE
    6To play
   5 No Q
 4   0 or 3 aces
 4   2 aces, no Q
 4NT   2 aces, Q