I made a rules enforcing preset for 12x12 Brawl Chess generated by the Play-Test Applet, apparently not needing to use the custom set, as I followed your advice about altering IDs and/or moves of pieces (in my case to match the labels of the Sac Chess group, Sac Chess: Standard piece set, which uses labels of one character per the 14 piece types).
When I tested the preset (see link below), in Move Mode, the (Omega) Pawns were allowed to move initially up to 3 squares. However, I tested a case where early on in a 'game' I played vs. myself I moved a Black pawn up to d5, then made White pawn do triple step e3-e6. At that point the preset indicated taking en passant to e4 by the Black pawn was allowed - but when I played the move I got a fatal error message.
[edit: I had some other bugs with the preset, but then I realized I fouled up a couple of table entries for the Applet, so I went back and re-did them, and re-did the possibly affected parts of the Applet's 12x12 setup diagram for Brawl Chess, and then generated Game Code for my preset again. After that only the preset's bug with Omega Pawns seems to have remained. edit2: it seems any form of en passant is recognized by the preset as a legal possibility, but then a fatal error message results when it is actually attempted to be played.]:
@ H.G.:
I made a rules enforcing preset for 12x12 Brawl Chess generated by the Play-Test Applet, apparently not needing to use the custom set, as I followed your advice about altering IDs and/or moves of pieces (in my case to match the labels of the Sac Chess group, Sac Chess: Standard piece set, which uses labels of one character per the 14 piece types).
When I tested the preset (see link below), in Move Mode, the (Omega) Pawns were allowed to move initially up to 3 squares. However, I tested a case where early on in a 'game' I played vs. myself I moved a Black pawn up to d5, then made White pawn do triple step e3-e6. At that point the preset indicated taking en passant to e4 by the Black pawn was allowed - but when I played the move I got a fatal error message.
[edit: I had some other bugs with the preset, but then I realized I fouled up a couple of table entries for the Applet, so I went back and re-did them, and re-did the possibly affected parts of the Applet's 12x12 setup diagram for Brawl Chess, and then generated Game Code for my preset again. After that only the preset's bug with Omega Pawns seems to have remained. edit2: it seems any form of en passant is recognized by the preset as a legal possibility, but then a fatal error message results when it is actually attempted to be played.]:
https://www.chessvariants.com/play/pbm/play.php?game=Brawl+Chess&settings=enf02