Drag and drop a PS3 game folder to ebootFIX.exe. For example drag&drop X:\GAMES\MY_GAME\PS3_GAME or X:\GAMES\MY_GAME or X:\GAMES\MY_GAME\PS3_GAME\USRDIR to ebootFIX.exe. It will create two PKG files and will decrypt+encrypt all executables (EBOOT.BIN and other .self files) to make them compatible with lower firmware versions.