Ok, I retried a clean installation using the lxqt iso, setting netinstall to yes and adapting the mirrorlist to the actual mirrors like in git-hub.
Calamares while trying to install the filesystem, gives me the following error(s):
Boost.Python-Fehler in job "initcpio".
<class 'subprocess.CalledProcessError'>
Command 'mkinitcpio -p linux' returned non-zero exit status 1.
Traceback:
File "/usr/lib/calamares/modules/initcpio/main.py". line 36, in run
run_mkinitcpio()
File "/usr/lib/calamares/modules/initcpio/main.py". line 28, in run_mkinitcpio
check_target_env_call(['mkinitcpio', '-p', kernel])
File "<string>", line 2, in <module>