So for clarification, run the EOScard program after the reformat on the PC before reinstalling the ML?
Reformat on PC _AND_ALSO_ low level format in camera, in that order both before EOScard.
EOScard sets the bootflag on the card, telling the camera that autoexec.bin is on the card, formatting removes the flag, so running the format after the EOScard would remove the flag which you need (that wasn't meant to sound patronising, I was just elaborating (which this will soon be in my unfinished tutorials)).
ALSO _important_, if you have run EOScard (if you have set the bootflag on the sd card) NEVER insert it into the camera without having "autoexec.bin" (and the ML folder) on the card. Because if it's not on the card the camera will still try to boot off the card which could damage or brick your camera.
If you do happen to, turn your camera off and remove the battery, then take the SD card out (switching the camera off by the power usually does nothing, so you need to remove the battery to turn the power off).