Yes, this firmware is very similar to 13xx HWID=972. But there is a difference, i.e. 13xx's firmware loads GIR (pictures, icons, etc.) from region 0x7F (fw_resources1.bin) while dnx520vbt's firmware loads it from 0:/Garmin/img_rsrc.gir.

So, instead of trying to randomly flash unrelated firmwares you can try a well-known way developed for 13xx from this thread: [Only registered and activated users can see links. ].
In particular, you can try the following post: [Only registered and activated users can see links. ]

After unpacking the archive to an SD card (I hope this device have an SD slot??), copy SD:/Updater/0972/ to SD:/Updater/1083/ and replace SD:/Updater/1083/ldr.bin with boot.bin from dnx520vbt's firmware, then insert the SD card to the device and restart it. When the update is finished, SD:/Updater/1083/update.log (post it here, please) and SD:/garmin/backup/16_BKP.bin (back it up and don't lose) should appear.


What do you know about WinCE? Do you know what's astlog.exe and if WinCE could save crashlog somewhere?