The correct query for opening the preset in Edit mode is &submit=Edit, not &edit=true.
The problem appears to be the fast castling, and now that I think about it, I believe I never implemented fast castling in the betza.txt GAME-code include file. So the entries in the legdefs table that would be interpreted by the JavaScript powering the Interactive Diagram as fast castling are mistaken for something that makes the GAME code crash.
For now I recommend commenting out the four lines that define the fast castling at the end of legdefs, like:
The King will then not be able to castle, but at least you can continue implementing the other aspects of the variant in the preset. In the mean time I will try to support fast castling in betza.txt. And when I have done that, you can uncomment the lines again.
The correct query for opening the preset in Edit mode is &submit=Edit, not &edit=true.
The problem appears to be the fast castling, and now that I think about it, I believe I never implemented fast castling in the betza.txt GAME-code include file. So the entries in the legdefs table that would be interpreted by the JavaScript powering the Interactive Diagram as fast castling are mistaken for something that makes the GAME code crash.
For now I recommend commenting out the four lines that define the fast castling at the end of legdefs, like:
The King will then not be able to castle, but at least you can continue implementing the other aspects of the variant in the preset. In the mean time I will try to support fast castling in betza.txt. And when I have done that, you can uncomment the lines again.