Got stuck in Libreboot on X200

[thlk]

Hello alltogether,

for some time i was using Linux Mint 19.1 on my X200.
Now i wanted to update to 20. but i did not choose to update but to completely install the system new.

Now unfortunately i got stuck at the beginning and the system won't boot any more. I could install Mint 20 from USB flash drive succesfully, but after installing it gets stuck.

vmlinuz is not found, and also i don't have the hd0, but the partitions have other names. Does someone have any clue, how to proceed?
Please see the two screenshots.

Any help appreciated.

URL to screenshots:

https://ibb.co/9N5yctk
https://ibb.co/THd4bb2

[thlk]

i updated the libreboot bios to the newest version, now it is working.