I don't think that solution works guys. My cards never have firmware files on them. Once the firmware is updated to the actual unit, it doesn't need to be on the card anymore, you can obviously take a brand new empty card and the firmwire will still work fine. I think the firmware files either self-delete from the original card after installation, or they're just removed the first time you reformat the card afterwards. Everytime I use any of my cards, there are only wav files on them and nothing more.
I'd like to have an answer to this as well, before I upgrade at all because then I would no longer have any other firmware to fall back on, just in case I encounter any "Card Error" problems or anything else. My original copies of the older firmware files were on a HDD that died, and I didn't think it was important enough to back up. Thanks if anyone knows something or can help.