Hi swartlkk,
hi members,

after 3 month it's done now: The engine runs fine, alternator works and abs is fine.

Let's summarise, what I replaced:

for ABS:

ABS Controller - Ok that was easy
all tires - because the front tires were worn out, as a result of the damaged braking system - the rear tires were worn out too, because of me

for alternator:

Electrifyer and regulator of the alternator - the regulator was the problem (but I payed for both)

for the engine:

spark plugs - nothing different
cables - nothing different
fuel filter - nothing different
distributor - nothing different
injector - a little bit smother running engine after (but not the reason for the misfire)
crankshaft balancer and seal - was leaking and made sounds
fuel pump - this was the reason for stuttering
crankshaft sensor - this was the reason for the warning light

I went to four different workshops, nobody had an idea or was able to analyse the reason. Not even the dealership...
I spent a lot of money and of my free time and it took 3 months.
Luckily I found some help here in the forum. - Just to get some idea about the problem. - Thanks again, swartlkk!

Hope, this helps others. - Check the crankshaftsensor first.

Regards - Hirni