wp-chessflash
to to the /wp-content/plugins/
directoryI recompiled chessflash.swf with a different piece set for use in Jin: merida.ead-01.zip. The original piece set didn't match the diagrams I use on the website of my chess club. You can replace chessflash.swf in the plugin directory with the original version to get the original pieces.
This is a problem in older versions of Firefox (prior to 3.6.2) with the wmode=transparent option for flash objects.