Hi Heiko,

I had a similar problem, except that I had a W580i that went dead after the SEUS. I used JDFlasher and recovered my phone by going to an older firmware - everything works great now.

As long as your Main, FS and Customization files are good, you should be able to recover the phone - of course, there might be other problems that I may not know.

Use the link below to check it out - it has a video tutorial too. Good luck.

JDflasher Flashing/Debrading/Customization Tutorial/Guide | SE Flashing

Sonu