I made a new release of Fairy-Max, making some tiny changes in the interpretation of initial double-pushes that allows them to be programmed also for non-Pawn pieces. As a result it has become possible to add Cambodian Chess as a variant. Because WinBoard does not support that, it has to be played as Makruk with legality testing off. A checkbox in the Engine Settings dialog decides if a game that you start will allow the extra initial King and Met moves that distinguish Cambodian 'Ouk' from Thai Makruk.
Falcon Chess has also been added as a variant.