After some practical experience with CCRL games, I'm less enthusiastic about their value to chess960 opening knowledge. The engines don't play with a book (meaning they don't 'learn') and they have no notion of what it means to follow a strategic opening plan. In my own games I have often found an initial move that none of the machines had played and that seemed like a reasonable move to me. After playing my own moves a few times and suffering no unexpected drawbacks, I stopped looking at the CCRL collection for ideas.
The CCRL thread discusses practical problems of engine vs. engine testing. For example,
I don't think you can get meaningful statistics by repeating the same starting positions with the same engines 100 times. Because there is a large chance of repeating the whole game or the beginning of the game. The engine you are using has particular understanding of particular positions. Even if there is sometimes variation in the chosen moves, the results are not statistically reliable to say something about the position itself. All you can say is that in [a certain engine's] understanding the position is usually won by White.
It's a good point. See the thread for more good points.