If you want to create opening books ASCII you have a good tool, frenzui of the programmer of frenzee.
It allows from a file pgn you to create the book, I make 2 books one for the lights and another one for the darks. In danasah I have used with permission of the author the old books ASCII that used (2 Mb), I believe that they are very good.
Now I have proven to make mine greater and I prove their operation, they are two book about 20 Mb, if you wish it you could use them.
I have also proven prodeo books now that the code is opened and although I have not played many games, seems that the result is slightly better with the books ASCII that I have created.
Also I have proven the PgnScanner tool and is very simple to make a book and to use it in a program (at least in C), although the results obtained have not been so good, I am going to propose the author to make some improvement in the selection of the move.
Control Eye - idea:
Etc 16. (even 9. ...) move and higher - engine not use book, but book moves little bonus in search tree, time cca 50% (cca depth -1) ?
Thank you Pavel for this gambit book . I am currently testing it with r*bk*.
Uff. My gambitbook not concept for computer opponents .
Some variants very incorrects ... , e.g.:
Ruy Lopez 3.-g5
French 3.c4 and 3.Be3
Greco 3.-f5
etc.
Maximum strenght computer opponents cca level Lokasoft engine.
If opponent Rybka, then 20% and higher results wonder! .
. I am currently testing it with r*bk*.
.