Hi Andrew,
There must be a lot of waiting around. Each team participates in 6 rounds, 4 rounds playing each of the others teams, and 2 rounds at the arcarde machine. However there must at least 10 rounds to allow everyone 2 chances at the arcade machine. The best solution would be to play only one of the arcade games, then it is possible to have a solution where at least 3 teams participate in every round.
G1 G2 G3 arcade
(B E) (---) (C D) -
(---) (A D) (---) B
(D E) (A B) (---) C
(---) (B C) (A E) D
(A C) (---) (B D) E
(---) (C E) (---) A
So above, A has a bye in round 1, C&E have a bye in round 2, and B&D have a bye in round 6. If you try to do something similar with only 5 rounds of play, then it cannot be arranged so that teams play each of the 3 games at least once and at most twice. I assume you want this, so I choose 6 rounds.
Hope that helps,
Ian