12 ominoes placed.
 1 2 3 4 4 4 4 4
 1 2 3 5 5 5 5 5
 1 2 3 6 6 6 6 6
 1 2 3 0 0 7 8 9
 1 2 3 0 0 7 8 9
 10 10 10 10 10 7 8 9
 11 11 11 11 11 7 8 9
 12 12 12 12 12 7 8 9

12 ominoes placed.
 1 1 1 1 1 2 3 4
 5 5 5 5 5 2 3 4
 6 6 6 6 6 2 3 4
 7 8 9 0 0 2 3 4
 7 8 9 0 0 2 3 4
 7 8 9 10 10 10 10 10
 7 8 9 11 11 11 11 11
 7 8 9 12 12 12 12 12

Done.  2 solutions found.