Bill,
If I understand you correctly, then each team plays each of 6 different types of game just once. The following schedule does exactly that.
Game1 Game2 Game3 Game4 Game5 Game6
Round 1: (L E) (D K) (B C) (A G) (H J) (I F)
Round 2: (C I) (B J) (G L) (F K) (D E) (A H)
Round 3: (H K) (G F) (A E) (D B) (I L) (C J)
Round 4: (F D) (L A) (K J) (I H) (C G) (E B)
Round 5: (A J) (I E) (F H) (L C) (K B) (G D)
Round 6: (B G) (C H) (D I) (E J) (F A) (K L)
Ian.
Puzzle for anyone interested: Can the schedule above be completed into a full round-robin tournament, with the property that rounds 6 to 11 would also be a solution to Bill's question?