While we waiting @Neo1984 to do the test with colors, let me acquaint you with one interesting (according to me) case.

The situation in short:
MK3 updated with latest software 3-1/63. I tried to change language and update with a custom one 3-1/65 (works perfect with many others MK3 and MK4), but after 30min waiting I had only black screen. I took CD out and tried v17 (clear, not 17.1) and update was successful.
Tried again, but with original v32 mode2 and i got only 15-20 resets and no loading of software.

Flash memory, in my opinion is OK, because I can change VIN, I can read nav, I can start language change, but it does not want to update.

I swap the mechanical part from working MK3 and.... nothing again.

Here is the log from NavCoder:
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