Sorry not to reply to this post until now; I didn't expect anyone would actually take interest.
Rich, to open the files you would need to leave the names as is and open them into a zip utility
(I used 7-Zip
). You might have to override the wildcard of the file open box to select them. In answer to your other question, using this utility, I was able to flash Coreboot onto the thin client. I also found a standard Phoenix BIOS image for this motherboard to flash on. The former was for running Linux which I am doing, but with the latter I presume I could've run XP if I had wanted to.
If you found a CE-only BIOS for your specific hardware, you could use any standard BIOS flasher for your motherboard to flash the image. Personally I would go for the DOS bootloader instead, as many thin clients do it that way too. The only reason I flashed the BIOS was to run Linux when the built-in BIOS only supported booting CE.