... going on with testing. Just BackUp, after that I do a full wipe and try to restore ...
Great! Thx man!
Did a backup, rebootet phone normal, then reboot in recovery. Format /system /data /cache - all ok - and after that a restore. Phone starts up and fully working.
Only the date from the backup is wrong. Is showing 12.01.1970 and also that's the name of the folder. But that doesn't matter.
Phone : Google Nexus 5 32GB Black - Rastakat
Phone : Google Nexus 4 16GB Black - Rastakat