I think I found the flag that has to be set to avoid the crash:
The 1st bit at offset 0x3F in TRE must be 1, not 0.
The wiki says about the meaning of this one byte field:
Flags: 0: detailed map, 1: transparent map, 2: show street before street
number, 3: show zip before city, 4-7: ?? When bit 0 is set routing is cancelled
Any hints where this flag might cause trouble?
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