Much as I enjoyed Chu, I've always wanted to play a variety of variants, so we can come back to it another time. I'd rather try a different game.

As for the zrf files, they have similar names if I remember correctly. It might be that when you unzipped some of the folders, you overwrote the files for another version of the game. I suggest unzipping them in separate subfolders within the rules folder for Zillions. You might have better luck keeping them better separated.

Back to what game to play, we could also try Wa shogi. It's 11x11. No one knows if historically it was designed with or without drops in mind, but it is playable both ways. Could be fun (and long, which I know appeals to you) if we played with drops. :)

http://www.zillions-of-games.com/cgi-bin/zilligames/submissions.cgi?do=show;id=1473

If you'd rather go larger, we could try Dai Dai. It's up to you.