Sounds like it might be a defective unit. Firmware would have no effect on a no picture scenario
Plug it into the set using the yellow plugs and see if you get a picture. If you do, set it to 720p and try again. If you still have nothing, the unit is defective and you should return it. If you're successful, configure it to go online and plug it into the net as the manual directs for the firmware update.
Failing that, you can put download it here and put it on the SD card or burn it to a disc.
http://panasonic.jp/support/global/c...5/bd55_na.html