Hi Radek,
For some reasons macOS High Sierra is giving some headaches around, but hey positive thinking there is always a solution!
Here are is an important question, did you do create a new USB media install with macOS High Sierra you're installing or does it come from another image? That could be one reason...
Otherwise if you're stuck, I would suggest to reboot with the option key and get out of the macOS install drive and reboot on your normal drive, it you still can and go to App Store download the macOS High Sierra available and recreate a USB media install...
Make your apfs drive with mac have only the container and the macos, so would be disk0, disk1, disk1s1. Macos installed as the sole OS on the ssd as apfs (only one drive connected at all) then i use disk utility to partition the device disk0 Select the drive (disk0) and click partition then click the + on the bottom left area of the drop down menu.
Otherwise internet recovery is a safe option...
Normally I would have suggested to use DiskWarrior but I know for a fact that it doesn't function properly on macOS Sierra...
Push comes to shove, if you've got an Apple store nearby, then make an appointment with a Genius, these guys are real wizards and most of the time, they can resolve issue so easily that it is really worth it not to forget about them!
Good luck...
Dec 15, 2017 1:30 PM