Hello. Thank you very much for your answer.
I made a new topic How to install OpenWRT on NanoPi R2S? - #5 by tom1995 where I described my actions and problems with the installation. You are right, I read that a lot depends on the quality of the SD card. I have a good SD card "Sandisk" class 10 and the installation process looks very strange, since FriendlyWRT loads without problems, as soon as I write OpenWRT to the same card, I can't load ...
I have more SD cards, I'll try...