the magic.disable_diskbootf flag does not work in the early pre-releases of ML 0.2 for the 60D. Once installed on the camera, there is no way to reset the boot flag in NVRAM without building a new autoexec.bin from source and modifying the debug.c code to ignore the value of that configuration option.
It appears to be an issue with how the configuration file is parsed - the log file indicates that the flag is read, but says ?unused about it as well.
the call to disable the boot flag does work, once if statement on line 644 of debug.c is removed.
if(disable_diskbootf != 0)