I'd read previously about some US/EU Nav VI's having the ghost-touch screen problem. Garmin has been replacing them without question, however i wasn't aware that they had issued a different HWID device 4044 for the problematic US/EU 2584. The fact they have changed the HWID indicates to me that they've also changed the firmware in some way and likely that's because they fitted a different screen, so that makes the 'old' 2584 firmware incompatible with the 'new' 4044 hardware. If so, flashing 2584 or 2842 system software (fw_all bin and, maybe, resources.bin) to the newer hardware would potentially make the 4044 screen inoperable. So great caution is needed regarding any ongoing action involving the old US/EU or the JN firmware to the point that i'd now seriously advise against that.

Likely all the various HWID models have the same PCB P/Ns (identical mainboard) and probably the localized firmwares use the same ramloader (boot.bin) with appropriate HWID and with different system firmware in fw_all.bin and perhaps also varying resources.bin data.

The same ramloader hypothesis is strongly supported by the fact your 4044 device hasn't died with 2842's ramloader written to region 12 even though the main system software of 4044 isn't booting.

IMPORTANT: Why are there two different Unit ID's in the update logs though, the UID shouldn't have changed. Do you have an explanation? Did you try to load an NV dump from your friend's 2842 device to your 4044? I hope not ...(shudder!). Or are those dumps from different units, your 4044 and your friend's 2842/s?

You might be able to safely write via Updater.exe the boot.bin of 2842 or 2584, by loading it as an *.RGN file with HWID first changed to 4044. That should then allow regions 5 and 43 to have the correct HWID written to them from rgn12 thus removing the HWID conflict between regions which is what i suspect is stalling the boot process. I'm assuming there that there's no material data difference in the various ramloaders but we MUST try to confirm that before you go further. If the only difference is the HWID written into the BIN files then it should be safe to try.

Could you please post copies of all 5.bin and 154.bin files you've dumped, clearly indicating which is from those two UIDs. Also please supply a link to the 2842's fw GCD. You can attach them to our server provided you RAR or ZIP them as max. size 15.07mb. Use the post editor behind "Go Advanced" to find the "Manage Attachments" button for that. You'll need to split the compressed GCD into several parts to attach, or just upload the single original file to MegaNZ, AnonFiles or Zippyshare. I already have the US/EU 2584 firmware to compare.