Crossword puzzle: chess-oriented and hard

Difficulty: high

Answers so far:

Across: 3.Orangutan, 5.Evans, 7.Trifunovic, 8.Tabiya, 11.Hippopotamus, 13.Remusat 15.Zebras

Down: 1.Blunder, 2.Triangulation, 4.Novelty, 6.Opposition, 9.Vienna, 10.Tarrasch, 12.Skewer, 14.Tempo

1 down is blunder.

 Right!

9 down is Vienna.
14 down is tempo.

3/3

Is 3 across orangutan without the "g" on the end.

4/4

7 across is Trifunovic.

5/5 - very good!

There are ten still left and these are tough.

15 across is Zebras.

13 across is Remusat.

7/7

10 down is Tarrasch.

8/8

That's over half the answers, I am the World Champion once again.

Yes, you can slow down now!

15 across is dummys

6 down is 'opposition'

 Good idea, but the answer was given correctly by Zankfrappa - "Zebras."