Not the HWID and SW version's problem, Garmin added another checker inside firmware.
I think the checker inside all non-english model.
I am checking TWN firmware, need a little time.
The problem is:
After run english firmware on non-english model, the non-english model will report software missing too.
Only run! not flash english firmware to non-english model!
I can convert OREGON 450&550 USA to CHN version, the newest CHN version is 2.30.
I think pureblue got factory firmware from garmin.
These filename is like as map of NAND chip.
Thanks turboccc, I use your GIR_Editor to modify startup logo of OREGON.
hello ! Do u have firmware file of OREGON 550 CHN version ? THX!