I released Cheese 1.9.1 to fix a problem with illegal moves played in rare cases when using FEN for start positions.
http://cheesechess.free.fr/en/download.htmlNow I print an error message when receiving illegal moves from the GUI.
This should never happen, but the message will help to find eventual problems in a GUI or Cheese move validation.
I don't expect an ELO change between 1.9 and 1.9.1.
Thanks to Volker Pittlik for reporting this problem.