Have you tried to turn on the emergency fast-brake flashers? Do they work and how sensitive are they during braking?

Select 09 (Central Electronics)
Function 07
Byte 17, Bit 0 Emergency Brake Flash Light active

Without knowing exactly what function it controls, what it might affect, and how to determine if the effect is desirable or not, I don't experiment with the computer settings. I'll leave adjusting values or flipping bits based on badly translated German up to others.