The spellZone can now also be B, R or Q. The spell then affects the first piece in each of the corresponding directions, which need not be adjacent. This was needed to implement pieces like the Gorgon, which immobilize pieces in a Queen range.
I extended the effect of the castleFlip parameter (which interchanged the meaning of left and right for black on a Betza castling descriptor when set to 1) to all moves. This seemed more logical. Note that castleFlip is generally needed on asymmetric castlings (like in Janus Chess or the CwDA Clobberers) in a mirror-image setup, and was already set automatically when symmetry=mirror was in effect. The old behavior was that with other moves the black pieces would be rotated. Which caused problems when pieces with left-right asymmetry were used in mirror-symmetric setups.
Some more tweeks: