Recent versions of Fairy-Max allow the nottation FxR=D in the line of the game definition that sepecifies the board size. The number D after the equal sign specifies the depth of the zone. In case this number is larger than 2 it also assumes that the Pawns start at the foremost rank in the zone. So for Camboian Chess and Makruk the game definitions specify 8x8=3. (A negative number there redefines the Pawn rank without affecting the zone size, and its absolute value then indicates the number of ranks behnd the Pawns. So Grant Acedrex uses 12x12=-3.)
The depth of the promotion zone icannot be independently set in WinBoard, but follows from the parent variant. So you would have to pick a parent variant that has a zone depth of 3, rather than 'fairy' (which has only promotion on the last rank). Variant 'elven' could be good for this.
Castling will be a problem. This is related to the way position setup works in Fairy-Max: it only assumes castling is possible if the piece on which such a move is defined, and the pieces on the edge of the same rank, start in the same location as what was defined as the start position. And in the current version of Fairy-Max start positions can only have pieces on the back rank, plus a single rank of Pawns.
Recent versions of Fairy-Max allow the nottation FxR=D in the line of the game definition that sepecifies the board size. The number D after the equal sign specifies the depth of the zone. In case this number is larger than 2 it also assumes that the Pawns start at the foremost rank in the zone. So for Camboian Chess and Makruk the game definitions specify 8x8=3. (A negative number there redefines the Pawn rank without affecting the zone size, and its absolute value then indicates the number of ranks behnd the Pawns. So Grant Acedrex uses 12x12=-3.)
The depth of the promotion zone icannot be independently set in WinBoard, but follows from the parent variant. So you would have to pick a parent variant that has a zone depth of 3, rather than 'fairy' (which has only promotion on the last rank). Variant 'elven' could be good for this.
Castling will be a problem. This is related to the way position setup works in Fairy-Max: it only assumes castling is possible if the piece on which such a move is defined, and the pieces on the edge of the same rank, start in the same location as what was defined as the start position. And in the current version of Fairy-Max start positions can only have pieces on the back rank, plus a single rank of Pawns.