should work with a usb ( the unit is a 7020 ??)
make sure once your log into the unit with flash wizard that ask it to recheck the hdd/usbcf card etc so it re reads it to make sure they are there.
then i always get flashwizard to do the format (i use a cf card ) then when you install the extra images make sure you tell it where to install.
on reboot it will pop up the flash wizard and have the other images listed to select from
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