Some devices write quite slowly to the card, Fa_Piter has had more experience than me with outdoor/tracking Garmins so take his advice. Keep in mind that when dumping a populated region even blank space is read so in the case of region 48 it's a lengthy process (that's the entire visible file system allocated space, aka it's internal flash memory which might be 2 gigabytes) Maybe if you more fully understand this particular process we're undertaking, what you've reported in Post #177 will then make more sense to you:
  • We're using Updater.exe only to initiate the text commands on the sd card, so once the flashing starts ("Loader" on device screen) the communication is between the device and card directly.
  • Updater initially reported "The Garmin device is not responding ....", which means the Alpha had already exited preboot simply because you had not been quick enough to click 'Ok' (you may have only a very brief opportunity to do that).
  • It reports the version software difference as a normal feature, you'd told me you used V3.00 to make the cure fw but it seems you used V3.20 (that's of no great concern but i can remake the RGN file with V3.20 to eliminate that message if it repeats ongoing and delays starting the text commands).
  • Just leave it undisturbed while 'Loader' shows on it's screen, don't disconnected from PC because even though Updater.exe's task is finished, the USB cable can keep supplying power in case of a weak battery.
  • Nowhere near all possible 255 regions are populated and some won't even exist on that device, others may exist but will still dump empty BIN files like you've seen. Those regions are not of interest provided the results are expected. The main ones which may give the secret of what's happened to this device are regions 14, 41 and 48 most likely so their contents are best known ongoing, but i'll like to see what else is dumped.

Old Chinese proverb (allegedly): "Softy softly catches monkey". I'm intentionally taking this slowly so as not to do further harm to an already quite tortured device. Actually, likely conventional advice would be to just fix region 14 by overwriting it with a healthy fw_all.bin and if that didn't work to then completely erase regions 48 and 41. I think it will likely come to one, more or all of those, but i'd rather know what's in all the operable regions beforehand.