Thank you for your advice

The slurry worked fine on all previous prints. With thinner slurry, i got lifting edged from time to time. Since i made it a thicker mixture, i hat no failures like this.

In regards to the temps:
With lower Temps at the hotend, i had extraction-problems. I might try to lower them again some time later to see, if i can tweak it.
The 120° Bed-Temp was because i had adhesion-problems with lower temps. During printing, the bed is at about 115°.

I will try a print with "minimum time for a layer" increased.
This should help, i think.
Will post the results later.