Note that while this method may work on your product, bootloaders since the mid-2000s have supported simpler ways to accomplish this task, as listed above.
IMPORTANT: The following instructions are for a Bitsy system with 32MB flash and a flash disk that starts at 16MB.  
Every CE build has a different starting location, as determined in the registry.  E.g.:
[HKEY_LOCAL_MACHINE\Drivers\BuiltIn\FlashFX]
    "Start"=dword:1400000
    "Length"=dword:C00000
Make sure to use the correct start and ending addresses, or you may erase the CE image, boot code, or both.